tag:theconversation.com,2011:/institutions/cancer-council-australia-985/articlesCancer Council Australia2018-03-20T03:30:52Ztag:theconversation.com,2011:article/918502018-03-20T03:30:52Z2018-03-20T03:30:52ZWhy does Australia have so much skin cancer? (Hint: it’s not because of an ozone hole)<figure><img src="https://images.theconversation.com/files/208115/original/file-20180227-36700-648hek.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">White people are not made for Australia's weather conditions.</span> <span class="attribution"><span class="source">from www.shutterstock.com</span></span></figcaption></figure><p><em>This article is part of our <a href="https://theconversation.com/au/topics/skin-series-50414">series about skin</a>: why we have it, what it does, and what can go wrong. Read other articles in the series <a href="https://theconversation.com/au/topics/skin-series-50414">here</a>.</em></p>
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<p>Skin cancer is one of Australia’s most common cancers, with data showing <a href="https://wiki.cancer.org.au/skincancerstats/Skin_cancer_incidence_and_mortality">almost a million</a> cases of skin cancer in 2015. </p>
<p>Skin cancer is primarily caused by excessive exposure to ultraviolet (UV) radiation from the sun, causing DNA damage to skin cells. If this damage is not repaired by the body’s internal DNA repair machinery, then faulty cell replication can occur – triggering the abnormal growth of cells – which <a href="http://www.publish.csiro.au/book/7227">eventually become cancers</a>. </p>
<p>People with pale skin types are more vulnerable to skin cancer and, broadly, the more sun they are exposed to – and the greater the intensity of the UV radiation – the higher their risk.</p>
<p>Cutaneous malignant melanoma is the most aggressive skin cancer claiming more than 1,700 lives in 2016. Squamous cells carcinoma and basal cell carcinoma are far more common but far less life threatening. Despite being very amenable to treatment if identified at an early stage, squamous cells carcinomas still caused 560 deaths in 2016. </p>
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Read more:
<a href="https://theconversation.com/sun-damage-and-cancer-how-uv-radiation-affects-our-skin-34538">Sun damage and cancer: how UV radiation affects our skin</a>
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<p>International comparisons highlight the extent to which we and our Kiwi friends are undisputed world champions in skin cancer. Unfortunately, we’ve long occupied gold and silver on the skin cancer Olympic podium.</p>
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<p><iframe id="8dMRN" class="tc-infographic-datawrapper" src="https://datawrapper.dwcdn.net/8dMRN/1/" height="400px" width="100%" style="border: none" frameborder="0"></iframe></p>
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<p>A conservative estimate of the cost of treating melanoma in Australia <a href="https://www.ncbi.nlm.nih.gov/pubmed/28756584">exceeds A$270 million</a> annually. If we add non-melanoma skin cancers (now called “keratinocyte cancers” after their cell of origin) and the bill is likely <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4871202/">more than A$1billion</a> a year.</p>
<h2>Why us?</h2>
<p>Most Australians (and Kiwis) have the wrong type of skin for their environment. Basically, through migration, our two countries have been populated by many people with fair skin whose ancestors come from much less sunny climates. Lack of protective pigmentation leaves skin cells especially vulnerable to the DNA-damaging rays from the sun. </p>
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Read more:
<a href="https://theconversation.com/common-skin-rashes-and-what-to-do-about-them-91518">Common skin rashes and what to do about them</a>
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<p>During human evolution, our early hominid ancestors in Africa lost their covering of body hair and developed pigmented skins, presumably as protection against the harsh tropical sun. With subsequent migration out of Africa into Europe, the protective benefits of dark skin became less important for survival and were likely a hindrance to effective vitamin D production. There was selective pressure for <a href="http://www.pnas.org/content/pnas/107/Supplement_2/8962.full.pdf">less pigmented skin with more distance from the equator</a>. </p>
<p>In contrast, those who migrated out of Africa to Asia, Australia and the islands of Melanesia were constantly exposed to sunlight. So they retained their protective pigmentation. This explains why the recent European migrants to the Americas and Oceania arrived in the “new worlds” with skin types <a href="https://www.sciencedirect.com/science/article/pii/S0022202X15356025">poorly suited to their new environments</a>. This was in stark contrast to the well-adapted skin of the indigenous inhabitants. </p>
<p>While melanin provides <a href="https://www.ncbi.nlm.nih.gov/pubmed/?term=Fajuyigbe+D+Su+M.+Lwin+Diffey+bl+baker++Tobin+Young">protection against the damage caused by exposure</a> to UV radiation, it’s not a “suit of armour”. <a href="https://www.aihw.gov.au/getmedia/0368fb8b-10ef-4631-aa14-cb6d55043e4b/18197.pdf.aspx?inline=true">Melanoma rates are far lower</a> in people with pigmented skin such as Aboriginal people, but not non-existent.</p>
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<a href="https://images.theconversation.com/files/208116/original/file-20180227-36696-12y3dfq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/208116/original/file-20180227-36696-12y3dfq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/208116/original/file-20180227-36696-12y3dfq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=421&fit=crop&dpr=1 600w, https://images.theconversation.com/files/208116/original/file-20180227-36696-12y3dfq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=421&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/208116/original/file-20180227-36696-12y3dfq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=421&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/208116/original/file-20180227-36696-12y3dfq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=529&fit=crop&dpr=1 754w, https://images.theconversation.com/files/208116/original/file-20180227-36696-12y3dfq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=529&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/208116/original/file-20180227-36696-12y3dfq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=529&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Melanin, which pigments the skin, protects against UV radiation. This is why paler people will get more skin cancer.</span>
<span class="attribution"><span class="source">from www.shutterstock.com</span></span>
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<p>A major factor is geography – that is proximity to the equator (the line on the globe that gets the greatest amount of sun). Generally speaking, the closer to the equator someone lives, the greater the amount and intensity of sun exposure they receive. That gradient is seen in a comparison of <a href="https://www.aihw.gov.au/getmedia/0368fb8b-10ef-4631-aa14-cb6d55043e4b/18197.pdf.aspx?inline=true">skin cancer rates across Australian states</a> with Queensland reporting much higher rates than New South Wales, which is in turn higher than Victoria. </p>
<p>Another is the <a href="https://www.space.com/14142-earth-closest-approach-sun-perihelion.html">earth’s elliptical orbit around the sun</a>. The planet is about 1.7% closer to the sun in January, during the southern summer, and 1.7% further away in July – northern summer. So that means when the sun is strongest the southern hemisphere is 3.4% closer to the sun than the north is during their summer. This increases UV by about 7%.</p>
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Read more:
<a href="https://theconversation.com/four-of-the-most-life-threatening-skin-conditions-and-what-you-should-know-about-them-92610">Four of the most life-threatening skin conditions and what you should know about them</a>
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<p>Add to that the lower pollution levels and clearer air in the southern hemisphere – due largely to much lower population densities – resulting in UV levels about 7% higher than in the northern hemisphere. </p>
<p>Taking all these factors together, <a href="https://theconversation.com/how-does-the-ozone-layer-protect-earth-from-radiation-9206">southern hemisphere locations receive about 15% more UV radiation</a> than the equivalent northern latitude location in any given year.</p>
<h2>What about the ozone hole?</h2>
<p>Many believe the ozone hole – a naturally-occurring pool of ozone-depleted air arising over the poles – explains much of our excess skin cancer rates. Stratospheric ozone does reduce the amount of UV reaching the Earth’s surface. When the ozone layer was damaged by the release of CFCs and halon from refrigerants from the 1960s onwards, more UV reached ground level. </p>
<p>So the depletion of the ozone layer caused legitimate concern and prompted the establishment of the <a href="https://theconversation.com/setting-a-good-example-australia-and-the-ozone-layer-9248">“Montreal protocol”</a> designed to eliminate ozone-damaging pollutants and repair the ozone hole. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/208118/original/file-20180227-36686-bc9mm2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/208118/original/file-20180227-36686-bc9mm2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/208118/original/file-20180227-36686-bc9mm2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=440&fit=crop&dpr=1 600w, https://images.theconversation.com/files/208118/original/file-20180227-36686-bc9mm2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=440&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/208118/original/file-20180227-36686-bc9mm2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=440&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/208118/original/file-20180227-36686-bc9mm2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=553&fit=crop&dpr=1 754w, https://images.theconversation.com/files/208118/original/file-20180227-36686-bc9mm2.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=553&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/208118/original/file-20180227-36686-bc9mm2.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=553&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Most people think our rates of skin cancer are due to a ‘hole’ in the ozone layer, but this isn’t really the case.</span>
<span class="attribution"><span class="source">from www.shutterstock.com</span></span>
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<p>As the ozone hole over the south pole breaks up in spring, pockets of ozone depleted air drift across Tasmania, southern Victoria and the southern part of New Zealand’s south island. The effects are minor and transient, and are being closely <a href="https://ozonewatch.gsfc.nasa.gov/SH.html">monitored by NASA</a> and other agencies.</p>
<p>In reality, ozone depletion has made no appreciable difference to skin cancer rates in Australia and New Zealand. The quantum of additional UV exposure was modest – and at a time of year when most skin was covered so as to stay warm. Happily, the Montreal Protocol has proven successful in facilitating ozone repair.</p>
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Read more:
<a href="https://theconversation.com/the-skin-is-a-very-important-and-our-largest-organ-what-does-it-do-91515">The skin is a very important (and our largest) organ: what does it do?</a>
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<h2>Are we making any headway?</h2>
<p>Melanoma rates in the under 40s age group (those who grew up with “Slip Slop Slap”) are coming down. This makes sense given the timing of the programs and the decades-long lag between protecting our skin and the benefits of “avoided” skin cancers. But rates in the 60+ age group are still going up and as a result so are the overall rates. We anticipate and hope those will fall over the next decade.</p>
<p>Comparisons with NZ suggest they have a lot to learn from our skin cancer messaging campaigns. But we both still have a long way to go to decrease the burden of skin cancer.</p><img src="https://counter.theconversation.com/content/91850/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Terry Slevin works for Cancer Council Western Australia (CCWA). CCWA attracts program funding from the WA Department of Health and Healthway to conduct skin cancer prevention programs, and he has contributed to many research initiatives on skin and other cancers, which have been funded by NHMRC, and Healthway. He is editor of "Sun Skin and Health", a book by CSIRO Publishing 2014.
He is affiliated with Cancer Council Australia, as Chair of the Occupational and Environmental Cancer Committee and Deputy Chair of the Public Health Committee. </span></em></p><p class="fine-print"><em><span>David Whiteman is Deputy Director of the QIMR Berghofer Medical Research Institute. He receives project and fellowship funding from the National Health and Medical Research Council of Australia, and project funding from Cancer Council Australia.</span></em></p>Most Aussies think we have such high rates of skin cancer due to an ‘ozone hole’. But that’s not the case. Here’s why we have nearly a million cases of skin cancer per year.Terry Slevin, Adjunct Professor, School of Psychology, Curtin University; Education and Research Director, Cancer Council WA; Chair, Occupational and Environmental Cancer Committee, Cancer Council AustraliaDavid Whiteman, Professor and Group Leader at the Cancer Control Group, QIMR Berghofer Medical Research InstituteLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/888692018-01-07T19:09:59Z2018-01-07T19:09:59ZExplainer: how does sunscreen work, what is SPF and can I still tan with it on?<figure><img src="https://images.theconversation.com/files/199186/original/file-20171214-27562-jt433n.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Sunscreen protects from skin cancer, burning and from the sun's ageing effects.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/thenickster/14368926652/in/photolist-nTJvhG-fpA68L-98dQzd-riRP91-snfAhe-4XHaqt-523knG-4aGwii-6RWoNM-9uXwko-8mBLqB-dUhHiP-9y1To8-51Y6Qe-e9KsRV-7ywGz1-9y4RKd-sVeqzj-b2TKxn-6TMieA-ac96Po-9WX1Gz-9y1TFp-F9M8w-bqfzVF-5cpJwZ-sVkZNF-eRPTDz-9XhCSX-ZPSFw8-sfYThZ-nZKFus-a5ExNL-9Ts6Kr-5bLjth-6ZQscZ-sVd7tj-hSD3Wz-Cqa5t-5q9c24-6q7nCD-cchSyy-7re8qy-2XD2jU-a5ZE3k-5A6DbJ-FSXmKV-6S9ZTw-5Rzq8d-y6XrR2">PRONicki Dugan Pogue/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>Sunscreen use not only <a href="https://www.ncbi.nlm.nih.gov/pubmed/10475183">reduces the risk</a> of <a href="https://www.ncbi.nlm.nih.gov/pubmed/21135266">skin cancer</a> and sunburn, it also <a href="http://annals.org/aim/article-abstract/1691733/sunscreen-prevention-skin-aging-randomized-trial">reduces the ageing effect</a> of the sun.</p>
<p>But whenever summer rolls around, it’s easy to forget the basics – like, how should I apply sunscreen? How long should I wait after applying it to go in the sun, and how long can I stay in the sun with it on? And how does it work anyway?</p>
<h2>How does sunscreen work ?</h2>
<p>There are two main parts to all sunscreens. The active ingredient and the emulsion.</p>
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<a href="https://images.theconversation.com/files/199538/original/file-20171217-17854-4k3d6x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/199538/original/file-20171217-17854-4k3d6x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/199538/original/file-20171217-17854-4k3d6x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/199538/original/file-20171217-17854-4k3d6x.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/199538/original/file-20171217-17854-4k3d6x.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/199538/original/file-20171217-17854-4k3d6x.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/199538/original/file-20171217-17854-4k3d6x.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/199538/original/file-20171217-17854-4k3d6x.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Sunscreens either absorb UV radiation or reflect it.</span>
<span class="attribution"><span class="source">from shuttersrock.com</span></span>
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<p>The active ingredient does the sun protection work. These come in two categories: UV absorbers and UV reflectors.</p>
<p>UV absorbers are chemicals that absorb UV radiation and convert it to a very low level of heat. So low most don’t notice it, but a small proportion of people do report sunscreens make them feel uncomfortably warm.</p>
<p>UV absorber chemicals are also called “organic”, because they contain carbon atoms, a basis for all organic matter. </p>
<p>Some absorb the UVB part of the spectrum, which is known to cause sunburn and contribute to skin cancer risk. Others absorb the UVA part of the spectrum. Recent research suggests the longer UVA wavelengths not only penetrate to deeper layers of the skin but <a href="https://www.ncbi.nlm.nih.gov/pubmed/21192263">contribute to skin cancer</a> through compromising immune response to DNA damage. </p>
<p>For that reason, sunscreen labelled “broad spectrum” is recommended as it offers the best protection.</p>
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<a href="https://images.theconversation.com/files/199537/original/file-20171217-17842-1nu28a7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/199537/original/file-20171217-17842-1nu28a7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/199537/original/file-20171217-17842-1nu28a7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=233&fit=crop&dpr=1 600w, https://images.theconversation.com/files/199537/original/file-20171217-17842-1nu28a7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=233&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/199537/original/file-20171217-17842-1nu28a7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=233&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/199537/original/file-20171217-17842-1nu28a7.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=293&fit=crop&dpr=1 754w, https://images.theconversation.com/files/199537/original/file-20171217-17842-1nu28a7.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=293&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/199537/original/file-20171217-17842-1nu28a7.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=293&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">Broad action sunscreen is recommended.</span>
<span class="attribution"><span class="source">from shutterstock.com</span></span>
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<p>UV “reflectors” are mostly made up of oxides, like zinc oxide and titanium dioxide, that absorb and scatter UV radiation.</p>
<p>There is normally more than one and often up to six or more active ingredients in most sunscreens.</p>
<p>The emulsion – the lotion, milk, cream, oil, foam or gel – is what carries the active ingredient. It is usually made up of some combination of oil and water, plus other goodies. These are important as they preserve the product so it lasts on the shelf or in your cupboard. They also help with water resistance, influence how the sunscreen feels and smells, and how well it binds to the skin. </p>
<h2>What does SPF mean and how is it measured?</h2>
<p>Sunscreen provides a <em>screen</em>, not a <em>block</em>. Think of a fly-screen door: air gets though but flies don’t. In the same way, the sun lotion or potion of your choice allows some small amount of UV radiation onto your skin.</p>
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<a href="https://images.theconversation.com/files/199539/original/file-20171217-17845-cclwbq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/199539/original/file-20171217-17845-cclwbq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/199539/original/file-20171217-17845-cclwbq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=823&fit=crop&dpr=1 600w, https://images.theconversation.com/files/199539/original/file-20171217-17845-cclwbq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=823&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/199539/original/file-20171217-17845-cclwbq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=823&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/199539/original/file-20171217-17845-cclwbq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1034&fit=crop&dpr=1 754w, https://images.theconversation.com/files/199539/original/file-20171217-17845-cclwbq.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1034&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/199539/original/file-20171217-17845-cclwbq.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1034&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
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<span class="caption">A sunscreen with SPF 30 isn’t much lower in protection than SPF 50.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/jeepersmedia/17855705411/in/photolist-tcRa8R-9kKWpL-6dXBqN-8TRiSp-5CHmuS-g3ZVFe-3QpNR-qpT9wg-aN6iE4-aN6iVB-cCmuPJ-sfYSRP-tatAWL-tcxKcQ-tcR94M-9TssdX-5ASZLL-FcMoR-UBeywg-BeYxS-3ePfsz-9XveSu-5gsrSr-6aeQL6-tatFdm-5dUxds-aijESW-9dv4iy-69RaLZ-8tjcm-7P58Gv-7U28y3-iiAcC-e7kULf-59CnVh-3e3mz-nVDFC7-LqfSm-Pp294-fDzbrd-8uao9D-6zCwUa-jk7Vw-i7oaU-cyWnfy-4TkmU6-5iAymk-43h1b-6ngGtx-eeWN4t/">Mike Mozart/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
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</figure>
<p>SPF stands for sun protection factor. It’s the measure of how much UV gets through the screen. The higher the number, the less UV passes through.</p>
<p>An SPF of 30 allows one-thirtieth or 3.3% of UV to reach your skin. This means it filters 96.7% of UV. With an SPF of 50, 98% is filtered and one-fiftieth or 2% gets through. </p>
<p>So while the difference between SPF 30 and SPF 50 sounds like a lot – it is a <a href="https://theconversation.com/mondays-medical-myth-spf50-sunscreen-almost-doubles-the-protection-of-spf30-3949">pretty modest</a> (1.3%) - difference in protection.</p>
<p>Put another way, if your unprotected skin would take ten minutes to show signs of burning, then <em>properly</em> applying SPF 30 sunscreen would slow the rate of burning to the point where it would take 30 times longer, or 300 minutes in total. SPF 15 would take 150 minutes, while SPF 50, 500 minutes. </p>
<p>But this is perfect world stuff. If you extend your stay in the sun for 500 minutes (over eight hours!) only relying on sunscreen, you will very likely still burn!</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/explainer-what-happens-to-your-skin-when-you-get-sunburnt-53865">Explainer: what happens to your skin when you get sunburnt?</a>
</strong>
</em>
</p>
<hr>
<h2>When and how do I put it on?</h2>
<p>At a microscopic level, the skin is a series of peaks and troughs. Layering on sunscreen around 20 minutes before going into the sun allows the product to flow into the troughs and bind properly to the skin. </p>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/199540/original/file-20171217-17860-dsx3hp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/199540/original/file-20171217-17860-dsx3hp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/199540/original/file-20171217-17860-dsx3hp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=353&fit=crop&dpr=1 600w, https://images.theconversation.com/files/199540/original/file-20171217-17860-dsx3hp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=353&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/199540/original/file-20171217-17860-dsx3hp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=353&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/199540/original/file-20171217-17860-dsx3hp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=444&fit=crop&dpr=1 754w, https://images.theconversation.com/files/199540/original/file-20171217-17860-dsx3hp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=444&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/199540/original/file-20171217-17860-dsx3hp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=444&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">The skin is a series of peaks and troughs.</span>
<span class="attribution"><span class="source">from shutterstock.com</span></span>
</figcaption>
</figure>
<p>Many sunscreens recommend reapplying every two hours. But another way to look at it is like painting a wall of your house. The first coat gets a reasonable coverage, but a reapplication 20-30 minutes after being in the sun – after the first coat has “dried” – gets you much more reliable coverage. And this will cover the bits you may have missed, or covered too thinly, on first pass.</p>
<p>Also, use it generously. Most people <a href="http://www.bmj.com/content/313/7062/942.1">use too little</a> (between a quarter and three-quarters) of the amount of sunscreen necessary to achieve the sun protection claimed on the label. A teaspoon per limb is a good rule of thumb. Add another teaspoon for your face, front and back. This comes to <a href="https://www.ncbi.nlm.nih.gov/pubmed/?term=Schneider+J+sunscreen+2002">seven teaspoons</a> (35ml) in all if you are at the beach in board shorts or a bikini.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/199541/original/file-20171217-17863-xjgjtl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/199541/original/file-20171217-17863-xjgjtl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/199541/original/file-20171217-17863-xjgjtl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=856&fit=crop&dpr=1 600w, https://images.theconversation.com/files/199541/original/file-20171217-17863-xjgjtl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=856&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/199541/original/file-20171217-17863-xjgjtl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=856&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/199541/original/file-20171217-17863-xjgjtl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1075&fit=crop&dpr=1 754w, https://images.theconversation.com/files/199541/original/file-20171217-17863-xjgjtl.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1075&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/199541/original/file-20171217-17863-xjgjtl.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1075&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">You need to apply around seven teaspoons of sunscreen in all if you’re at the beach in a bikini.</span>
<span class="attribution"><a class="source" href="https://unsplash.com/photos/W3nPLWO1ePU">Photo by rawpixel.com on Unsplash</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Layer it on and spread it around. Reapply every two hours or more often if you are active (sweating, towelling off, skin making physical contact with anything that might rub it off), even if the bottle claims four-hour water resistance. And a good idea is to check if the lotion hasn’t passed its use-by date. </p>
<p>Use other things to protect your skin too. Hats, shade, clothing and even staying indoors at the highest UV periods. The closer to solar noon, usually between midday and 12.30pm, the higher the UV. </p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/health-check-will-i-damage-my-eyes-if-i-dont-wear-sunglasses-68582">Health Check: will I damage my eyes if I don't wear sunglasses?</a>
</strong>
</em>
</p>
<hr>
<p>The World Health Organisation recommends protecting skin from the sun when the <a href="http://www.who.int/uv/publications/globalindex/en/">UV Index is 3</a> or above. The Bureau of Meteorology reports on the <a href="http://www.bom.gov.au/uv/">UV Index around Australia</a> and the <a href="http://www.sunsmart.com.au/tools/interactive-tools/free-sunsmart-app">SunSmart App</a> allows you to get live readings on your smartphone. </p>
<h2>How long can I stay in the sun with sunscreen on?</h2>
<p>It’s wise to stay in the sun no longer than is necessary to do your planned activity. Staying out longer just because you have the sunscreen “suit of armour” (which it is not) is a bad idea. </p>
<p>Even following all the best advice, the normal daily activity – wiping water from your eyes, scratching an itch, cuddling the kids, brushing against a tree or your best buddy – will remove sunscreen and diminish its performance. And remember it is screening, not blocking the sun.</p>
<p>And will you still get a tan if you put on sunscreen properly? Well, no. If sunscreen is properly applied to do its job of reducing UV radiation exposure, it prevents the biological process of tanning.</p>
<hr>
<p><em>Update: this article originally stated metallic particles reflect UV but in fact UV is scattered by oxides.</em></p><img src="https://counter.theconversation.com/content/88869/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Terry Slevin works for Cancer Council Western Australia (CCWA), and works with Cancer Council Australia (CCA). Cancer Councils sell sunscreen. Less than 5% of Cancer Council income is derived from sunscreen sales. CCWA received government grants to run the SunSmart program in Western Australia. He is editor of Sun Skin and Health (2014 CSIRO publishing). Proceeds of both sunscreen sales and the book go to cancer research, education and support for people with cancer.</span></em></p>Whenever summer rolls around, it’s easy to forget the basics of sunscreen. How long should I wait after applying it to go in the sun, and how long can I stay in the sun with it on?Terry Slevin, Adjunct Professor, School of Psychology, Curtin University; Education and Research Director, Cancer Council WA; Chair, Occupational and Environmental Cancer Committee, Cancer Council AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/836322017-09-08T00:03:42Z2017-09-08T00:03:42ZAlcohol increases cancer risk, but don’t trust the booze industry to give you the facts straight<figure><img src="https://images.theconversation.com/files/185075/original/file-20170907-8393-zzdja2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">We've known for over three decades that cancer risk increases with alcohol consumption.</span> <span class="attribution"><span class="source">from shutterstock.com</span></span></figcaption></figure><p>The alcohol industry has been misleading the public about the real link between alcohol and cancer, with tactics similar to those used by the tobacco industry. This is the finding from research published today in the <a href="http://onlinelibrary.wiley.com/doi/10.1111/dar.12596/full">Drug and Alcohol Review</a> journal. The misleading information is being passed off as health messaging to a public largely unaware that it’s coming from the industry itself.</p>
<p>For nearly <a href="https://monographs.iarc.fr/ENG/Monographs/vol44/mono44.pdf">three decades</a>, we have known cancer risk increases with alcohol consumption levels, on a dose-to-response basis. That is, the more we drink the greater the risk. </p>
<p>Back in 1988, the World Health Organisation’s cancer research arm concluded that alcohol consumption was a group one carcinogen – a direct cause of cancer in humans. In Australia in 2010, about 3,200 cases of cancer were <a href="https://www.ncbi.nlm.nih.gov/pubmed/26437723">attributable to alcohol</a> consumption.</p>
<p>And it doesn’t matter if you’re swilling shiraz at the Mosman Park Dinner Society or downing lager at the Bullamakanka Darts Club, it’s the alcohol, not the type of beverage, that does the damage.</p>
<hr>
<p><strong><em>Read more: <a href="https://theconversation.com/health-check-does-alcohol-cause-cancer-22959">Does alcohol cause cancer?</a></em></strong> </p>
<hr>
<p>Led by the London School of Hygiene and Tropical Medicine, the <a href="http://onlinelibrary.wiley.com/doi/10.1111/dar.12596/full">latest study</a> concluded:</p>
<blockquote>
<p>The [alcohol industry] appears to be engaged in the extensive misrepresentation of evidence about the alcohol-related risk of cancer. These activities have parallels with those of the tobacco industry.</p>
</blockquote>
<p>The authors pointed to three main strategies the industry uses to do this:</p>
<ul>
<li><p>denying, omitting or disputing the evidence that alcohol consumption increases cancer risk</p></li>
<li><p>distorting the evidence by mentioning cancer but misrepresenting the link, such as implying risk is present only with higher levels of drinking</p></li>
<li><p>distracting or diverting discussion away from the independent effects of alcohol on common cancers, such as mentioning alcohol is one of many causes. Breast and bowel cancer appeared to be particular targets for this type of misrepresentation.</p></li>
</ul>
<h2>Dodgy public health messages?</h2>
<p>The study assessed key messages provided by 27 organisations run, funded or controlled by the alcohol industry in English-speaking countries. Known as social aspects and public relations organisations, these bodies seek to shape consumer messaging about alcohol and seem to be gaining increasing resources and prominence. </p>
<p>One example of such an entity is the <a href="http://www.iard.org/about/members/">International Alliance for Responsible Drinking</a>. The research paper states that its members include some of the world’s leading beer, wine and spirits producers. </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/185077/original/file-20170907-8353-rplsbh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/185077/original/file-20170907-8353-rplsbh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/185077/original/file-20170907-8353-rplsbh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/185077/original/file-20170907-8353-rplsbh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/185077/original/file-20170907-8353-rplsbh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/185077/original/file-20170907-8353-rplsbh.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/185077/original/file-20170907-8353-rplsbh.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/185077/original/file-20170907-8353-rplsbh.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Industry messages often distort alcohol’s link to cancer.</span>
<span class="attribution"><a class="source" href="https://unsplash.com/search/photos/bartender?photo=YIUawXx7xm0">Photo by Artem Pochepetsky on Unsplash</a></span>
</figcaption>
</figure>
<p>The Australian example included in the study is <a href="https://drinkwise.org.au/">DrinkWise</a>. Its 13-member <a href="https://drinkwise.org.au/about-us/drinkwise-board-of-directors/">board</a> includes six alcohol industry representatives from groups such as the Distilled Spirits Industry Council of Australia, the Brewers Association of Australia and New Zealand and the Australian Hotels Association. DrinkWise <a href="https://drinkwise.org.au/about-us/about/#">says its</a> “primary focus is to help bring about a healthier and safer drinking culture in Australia”. </p>
<p>A <a href="https://www.ncbi.nlm.nih.gov/pubmed/28664575">recent survey</a> showed that, of the one in two people who had heard of DrinkWise, only around a third (37%) knew the alcohol industry funded it. </p>
<p>Drinkwise’s <a href="https://drinkwise.org.au/drinking-and-you/is-your-drinking-putting-you-at-risk-of-cancer/">message on alcohol’s impact on cancer</a> opens by saying alcohol is “one of a number of factors that contribute to the risk for developing certain types of cancer”. This is true. But some might consider this “distraction”.</p>
<p>The second message is:</p>
<blockquote>
<p>Cancer risk associated with the consumption of alcohol is related to patterns of drinking, particularly heavy drinking over extended periods of time. </p>
</blockquote>
<p>Again, technically true. But it avoids the fact low levels of consumption lead to low levels of risk increase. The research out today classified this as “distortion”.</p>
<hr>
<p><strong><em>Learn more about cancer risk: <a href="https://theconversation.com/interactive-body-map-what-really-gives-you-cancer-52427">Interactive body map</a></em></strong></p>
<hr>
<p>The way information is framed is essential to the message people take from it. And there’s little doubt the alcohol industry are masters of communication.</p>
<p>Information such as that given by DrinkWise may invite a drinker looking to avoid the thought their own drinking might increase their risk of cancer to think: “but other things are more important causes of cancer” and “I am not a heavy drinker over a long period of time so I am OK”. Conveniently, “heavy drinker” is not clearly defined.</p>
<p>Too few people know alcohol is a significant contributor to cancer, and this is a problem.</p>
<h2>Not enough know the link</h2>
<p>A <a href="http://www.publish.csiro.au/he/HE13081">survey conducted in 2008</a> in Western Australia found over 55% of adult women, when prompted, recognised a link between alcohol consumption and cancer risk. In the same survey, around 42% of women reported believing red wine consumption helped to prevent cancer.</p>
<p>A more <a href="http://www.tandfonline.com/doi/figure/10.1080/16066359.2016.1175557?scroll=top&needAccess=true">recent national survey</a> found 53% of adults linked alcohol with cancer risk. And funnily enough, just over half (52%) of those drinking at high or very high risk levels did not perceive their drinking to be harmful.</p>
<hr>
<p>
<em>
<strong>
Read more:
<a href="https://theconversation.com/social-acceptance-of-alcohol-allows-us-to-ignore-its-harms-10045">Social acceptance of alcohol allows us to ignore its harms</a>
</strong>
</em>
</p>
<hr>
<p>In 2010-11, the WA government ran an <a href="http://alcoholthinkagain.com.au/Campaigns/Campaign/ArtMID/475/ArticleID/8/Alcohol-and-Cancer-Spread-and-Stains">education campaign</a> to show how alcohol increased the risk of breast cancer. This <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4360807/">improved community awareness</a> of the link from 62% to 87%. It also led to more women reporting the intention to reduce their drinking.</p>
<p>Before the campaign, 10% of those who drank fewer than two standard drinks per day reported they intended to reduce drinking. This rose to 25% after seeing the campaign. Among those who drank more than two drinks a day, the figure went from 28% to 38.5%. </p>
<p>If these effects play out in the wider community through a national campaign, it may well result in a meaningful reduction in alcohol sales. Obviously, this is not in the industry’s interest.</p>
<p>Cancer is the <a href="https://www.ncbi.nlm.nih.gov/pubmed/7718649">most feared</a> illness. This is particularly so for middle-aged and older people who see their peers increasingly getting cancer diagnoses. And yet new research shows people in the <a href="https://theconversation.com/beer-bongs-and-baby-boomers-the-unlikely-tale-of-drug-and-alcohol-use-in-the-over-50s-82753">baby boomer generation</a> are the group least likely to be reducing their consumption.</p>
<p><a href="https://www.ncbi.nlm.nih.gov/pubmed/26787351">Research on health warnings</a> on alcohol labels suggests messages about the link between booze and bowel cancer have the greatest effect on making drinkers think twice. So should we be surprised the industry selling the product is keen to muddy the waters about what is a clear connection between drinking and cancer?</p>
<p>For too many people, the alcohol and cancer story is new news. The more we drink the more we increase the risk of cancer. </p>
<p>This is another inconvenient truth to add to the list. But we must all have the information to allow us to make the choice. And the alcohol industry is clearly not the best source of that information.</p><img src="https://counter.theconversation.com/content/83632/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Terry Slevin is employed by Cancer Council WA and is a spokesperson for Cancer Council Australia. He has received funding from research funding organisations and government agencies involved in promoting public health. </span></em></p>A new study has found the alcohol industry deliberately misrepresenting the cancer risk of alcohol, while passing it off as health messaging.Terry Slevin, Adjunct Professor, School of Psychology and Speech Pathology, Curtin University; Education and Research Director, Cancer Council WA; Chair, Occupational and Environmental Cancer Committee, Cancer Council AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/795722017-06-25T20:11:43Z2017-06-25T20:11:43ZThree charts on: cancer rates in Australia, where liver cancer is on the rise while other types fall<figure><img src="https://images.theconversation.com/files/175094/original/file-20170622-30227-39gmf0.jpg?ixlib=rb-1.1.0&rect=0%2C0%2C3994%2C2658&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The incidence of liver cancer is increasing and has the potential to become a national health crisis.</span> <span class="attribution"><span class="source">from shutterstock.com </span></span></figcaption></figure><p>Liver cancer is a looming health threat in Australia, recent findings from the Australian Institute of Health and Welfare’s (AIHW) <a href="http://www.aihw.gov.au/publication-detail/?id=60129559785">Burden of Cancer report</a> suggest. </p>
<p>While rates of other cancers are falling or remaining static, liver cancer is the only “top ten” cancer for which rates increased between 2003 and 2011.</p>
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<p>The “burden” of cancer is a measure also called “Disability Adjusted Life Years” (or DALYs), capturing quality and quantity of life. It combines the impact of the number of deaths (and how young people die) and number of people ill from a disease, accounting for how sick or disabled they are and for how long. This allows comparisons across different diseases. </p>
<p>Using “rates” allows comparisons across time, taking account of differences in population numbers and age profiles.</p>
<h2>Liver cancer crisis?</h2>
<p>While still not a common cancer, making up less than 1.5% of the 125,000 cancer cases diagnosed in 2013, liver cancer rates have <a href="http://www.aihw.gov.au/acim-books/">increased fivefold</a> since 1982. Action is required due to the <a href="http://ww2.health.wa.gov.au/%7E/media/Files/Corporate/general%20documents/WA%20Cancer%20Registry/The-Cancer-Effect-All-Cancers-Survival-2010-2014.ashx">poor five-year-survival rate</a> of less than 20%.</p>
<p>But why are diagnosis rates going up?</p>
<p>Unpublished work in progress, which builds on a <a href="http://onlinelibrary.wiley.com/doi/10.1111/azph.2015.39.issue-5/issuetoc">series of studies</a> by the Cancer Control Group at QIMR Berghofer Medical Research Institute in Brisbane, suggests liver cancer is caused by five main factors.</p>
<p>Tobacco smoking caused 365 liver cancer cases, or about 21% in 2013 in Australia. Hepatitis C virus contributed to 330 cases (19%) of liver cancer. Hepatitis B virus accounted for 281 cases (16%), alcohol 266 cases (15%) and obesity 451 (25%).</p>
<h2>What’s to blame?</h2>
<p><a href="http://www.aihw.gov.au/WorkArea/DownloadAsset.aspx?id=60129556763">Falling smoking rates</a> suggest liver cancer figures should have been have been higher in the past. Due to the lag time between when people smoked and cancer diagnosis, tobacco is still a leading driver of liver cancer. Current smoking trends leave us optimistic these rates may drop in the future. </p>
<p>Similarly, alcohol consumption is on a <a href="http://www.abs.gov.au/ausstats/abs@.nsf/Lookup/by%20Subject/4364.0.55.001%7E2014-15%7EMain%20Features%7EAlcohol%20consumption%7E25">modest decline</a> and is unlikely to explain the increase in liver cancer. </p>
<p>Obesity is a different story. Well-documented <a href="http://www.aihw.gov.au/WorkArea/DownloadAsset.aspx?id=60129556760">increases in overweight and obesity</a> will likely be a driver of liver cancer through the pathways of diabetes and non-alcoholic fatty liver disease, a condition where fat accumulates in liver cells. </p>
<p>But the major engine driving increased liver cancer is likely to be the rising prevalence of people infected with hepatitis B and hepatitis C viruses. Chronic hepatitis causes infection and inflammation of the liver, which can lead to scarring called cirrhosis. In some, this leads to cancer.</p>
<p>Around <a href="http://wiki.cancer.org.au/policy/Liver_cancer/Causes">450,000 Australians</a> live with either hepatitis B or hepatitis C. The two viruses are passed on in quite different ways. </p>
<p><a href="https://www.ncbi.nlm.nih.gov/pubmed/24090323">More than 90%</a> of people with hepatitis B virus were born overseas in countries where the virus is common, such as the Asia Pacific or sub-Saharan Africa. </p>
<p>Meanwhile, <a href="https://kirby.unsw.edu.au/sites/default/files/kirby/report/SERP_HepBandC-Annual-Surveillance-Report-Supp-2016.pdf">injecting drug users</a> dominate the 227,000 people with chronic hepatitis C virus in Australia, making up 57% of those affected. </p>
<h2>Liver cancer in Indigenous Australians</h2>
<p>Aboriginal people are another major group among which hepatitis B virus is endemic and hepatitis C is disproportionately common. High rates of viral infection in these communities (as in any community) are often untreated and tend to persist. This is especially the case when high rates of incarceration, needle sharing and other infection transmission behaviours occur. </p>
<p>While other causes of the disease are also at play, hepatitis rates are likely to be the main culprit to explain disturbing liver cancer rates in Australia’s First Nations people. It has become the third-most-common cancer in that group. </p>
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<h2>Other cancer deaths expected to rise</h2>
<p>Liver cancer is predicted to grow to become the fifth-most-common cause of cancer death in 2020 in Australian men and the sixth-biggest killer in women. This will eclipse melanoma as a cause of death.</p>
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<p>Higher death rates from pancreatic and brain cancers may be linked to a lack of successful treatment for these cancers. Increased pancreatic cancer mortality is also linked to smoking. Increased lung cancer mortality in women is linked to the higher uptake of smoking by women in the 1970s and ’80s. The elevated bowel cancer death rates expected in women do not take into consideration the effect of the government’s <a href="http://www.health.gov.au/internet/screening/publishing.nsf/Content/bowel-screening-1">National Bowel Cancer Screening Program</a>, which should soon start to show benefits in reduced mortality from that cancer.</p>
<h2>Averting the ‘crisis’</h2>
<p>Improved efforts to identify and treat people with hepatitis B and C viruses are required to combat liver cancer. </p>
<p>Infant vaccination for hepatitis B virus is making great strides, with <a href="https://kirby.unsw.edu.au/sites/default/files/kirby/report/SERP_HepBandC-Annual-Surveillance-Report-Supp-2016.pdf">participation rates exceeding 90%</a> in general and Indigenous populations. While this is good news, the challenge of reaching inbound migrant communities remains.</p>
<p>Needle exchange programs in prisons and outside are vital strategies to reduce needle sharing – the vehicle for much of the transmission of hepatitis C virus.</p>
<p>Efforts to reduce smoking, obesity and alcohol consumption are under way, but persistence is vital, especially in Indigenous communities. Tools are available to avert the “liver cancer crisis”, but we need to use them.</p><img src="https://counter.theconversation.com/content/79572/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Terry Slevin is employed by Cancer Council Western Australia and is affiliated with Cancer Council Australia and Curtin University. He is a Fellow of the Public Health Association of Australia (PHAA) and a Board member of the WA Health Promotion Foundation. He has been involved in funded cancer research programs on various topics over more than two decades. </span></em></p>While other cancer rates fall or remain static, liver cancer is on the rise. Here’s why we need to start paying attention.Terry Slevin, Adjunct Professor, School of Psychology and Speech Pathology, Curtin University; Education and Research Director, Cancer Council WA; Chair, Occupational and Environmental Cancer Committee, Cancer Council AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/639472016-09-09T04:34:16Z2016-09-09T04:34:16ZOne in five tattoo inks in Australia contain carcinogenic chemicals<figure><img src="https://images.theconversation.com/files/137121/original/image-20160908-16611-opufgy.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">But it's unclear what that means for cancer risk.</span> <span class="attribution"><a class="source" href="http://www.shutterstock.com/pic-324788036/stock-photo-master-tattoo-draws-the-orange-paint-on-the-clients-tattoo-tattoo-artist-holding-a-pink-tattoo-machine-in-black-sterile-gloves-and-working-on-the-professional-blue-mat.html?src=mTgEp9KFLcO7JiRH2LHaDQ-1-0">IvanRiver/Shutterstock</a></span></figcaption></figure><p>A <a href="https://www.nicnas.gov.au/communications/issues/Tattoo-inks">report</a> this week from the Australian government’s National Industrial Chemical’s Notification and Assessment Scheme (<a href="https://www.nicnas.gov.au/">NICNAS</a>) shows what’s in the ink that’s under the skin of more than <a href="http://www.mccrindle.com.au/the-mccrindle-blog/tattoos_in_australia_perceptions-_trends_and_regrets">2 million Australians</a> and about <a href="http://www.ncbi.nlm.nih.gov/pubmed/26211826">100 million Europeans</a>. And it’s not pretty.</p>
<p>The report found 471 different tattoo inks likely to be used in Australia made up of 89 unique chemicals. They interviewed 22 professional tattoo artists and sourced 49 specific tattoo inks likely to be used in Australian tattoo parlours for detailed chemical analysis.</p>
<p>Of the 49 inks NICNAS tested, only four complied with the <a href="https://wcd.coe.int/ViewDoc.jsp?p=&Ref=ResAP(2008)1&Language=lanEnglish&Ver=original&Site=CM&BackColorInternet=DBDCF2&BackColorIntranet=FDC864&BackColorLogged=FDC864&direct=true">European standards</a>. </p>
<p>The major concern was the presence of polycyclic aromatic hydrocarbons (PAHs), a group of chemicals <a href="https://monographs.iarc.fr/ENG/Monographs/vol92/mono92.pdf">known to be carcinogens</a>. PAHs were found in more than one-fifth of the samples tested and in 83% of the black inks tested.</p>
<p>Other non-compliant components include barium, copper, mercury, amines and various colourants.</p>
<p>In some inks, there was a mismatch between the content and the labelling.
One ink was sold and used for tattooing when the container label said it was not intended for this purpose.</p>
<p>Gone are the days of tattoos being seen only on bikies and sailors. Increasing proportions of the population have increasing proportions of the dermal layer of their skin injected with the multi-coloured artworks. There is no sign of demand dropping off.</p>
<p>This is an international challenge for <a href="http://www.ncbi.nlm.nih.gov/pubmed/22469126">regulators</a>. Italy, for instance, <a href="http://www.ncbi.nlm.nih.gov/pubmed/25833645">had an eight-fold increase</a> in the number of tattoo parlours from 2006 to 2015. Like us, they struggle to monitor what the effects might be. </p>
<p>Swiss health authorities <a href="http://www.bag.admin.ch/dokumentation/publikationen/01435/04412/05934/index.html?lang=de&sort=">analysed 416 ink samples</a> and found 39 colourants that were never tested for use in contact with the human body. </p>
<p>Traditional Maori tattoos (<a href="http://www.teara.govt.nz/en/ta-moko-maori-tattooing">moko</a>) are a treasure protected by the <a href="http://archives.govt.nz/exhibitions/treaty">Treaty of Waitangi</a>, so regulation in New Zealand has special challenges.</p>
<p>It’s important to remember that humans have been tattooing their skin <a href="https://www.raci.org.au/flipbook?id=101#page=8">for thousands of years</a> using various methods, some very crude. Outside the risks of infection from unclean injecting equipment, and some <a href="http://www.healthguidance.org/entry/14894/1/Reasons-NOT-to-Get-a-Tattoo.html">serious pre-existing medical conditions</a>, there is little evidence directly linking tattooing to serious illness. </p>
<p>However, a <a href="http://www.ncbi.nlm.nih.gov/pubmed/?term=klugl+i+hiller+k+tattoo">German study</a> found 67% of tattooed people reported complications. Of those, 7% were systemic (affecting more than just the skin around the tattoo) and 6% were persistent. These are mostly superficial skin infections but have included bacterial infections such as <a href="http://www.ucl.ac.uk/%7Ezchabg4/staphylococci.htm">staphlococci</a> and <a href="https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/streptococcal-infection-group-a">streptococci</a>, <a href="http://www.niaid.nih.gov/topics/mycobacteria/pages/default.aspx">mycobacteria</a> and, in some rare cases, blood-borne viruses such as <a href="https://theconversation.com/explainer-the-a-b-c-d-and-e-of-hepatitis-54739">hepatitis B and C</a>. </p>
<p>So what does all this mean? In short, <a href="http://www.ncbi.nlm.nih.gov/pubmed/26211826">no one really knows</a>. Will everyone with ink get cancer? No. But the basics of toxicology tell us that the harm any substance does is influenced by how “poisonous” the substance is, the circumstances and nature of the exposure, and the dose people are exposed to. </p>
<p>Is there a prospect that with more people getting more tattoos, cancers linked to this exposure will occur? Again, we don’t know.</p>
<p>Specific concerns that tattoos might cause or mask skin cancer seem – so far at least – <a href="http://www.ncbi.nlm.nih.gov/pubmed/22469126">unfounded</a>.</p>
<p>It seems timely to establish a study to follow up on those who have tattoos and how they fare compared with those with a “blank canvas”. The simple truth is, we have no idea what, if any, long-term health effects go with having tattoo ink injected into human skin.</p>
<p>Another complexity is the “DIY tattoo”. Controlling the ink administered by paid tattoo artists in identifiable businesses is one issue. Controlling the ink that comes through online shopping and is administered by enthusiastic amateurs at home is quite another.</p>
<p>So, if you already have tattoos, what should you do? Removing them may not help. The NICNAS report says:</p>
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<p>These chemicals can undergo photo degradation under exposure to … solar radiation and lasers.</p>
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<p>This means the chemicals, instead of being trapped under the skin, are released into the body. And it’s unclear what effect this might have. </p>
<p>As tattooing becomes increasingly mainstream, we need to ensure those who are considering getting tattooed are fully informed of the risks. And if they wish to proceed, we need to ensure they can do so as safely as possible. </p>
<p>Stopping the use of unsafe ink and related contaminants is a vital first move. This report from NICNAS is an important step towards us getting this house in order.</p><img src="https://counter.theconversation.com/content/63947/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Terry Slevin is Education and Research Director for Cancer Council Western Australia. He is also Chair of the Cancer Council Australia Occupational and Environmental Cancer Committee. He represents Cancer Council Australia on the Strategic Consultative Committee for The National Industrial Chemical Notification and Assessment Scheme (NICNAS) </span></em></p>Of the 49 inks tested, only four complied with the European standards. Carcinogens were found in more than one-fifth of the samples, and in 83% of the black inks.Terry Slevin, Adjunct Professor, School of Psychology and Speech Pathology, Curtin University; Education and Research Director, Cancer Council WA; Chair, Occupational and Environmental Cancer Committee, Cancer Council AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/580632016-06-06T20:06:44Z2016-06-06T20:06:44ZHow Australians Die: cause #2 – cancers<figure><img src="https://images.theconversation.com/files/122434/original/image-20160513-27184-134upnp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Age-standardised cancer death rates have been falling in Australia.</span> <span class="attribution"><span class="source">from shutterstock.com</span></span></figcaption></figure><p><em>This is the second in the <a href="https://theconversation.com/au/topics/how-australians-die">How Australians Die</a> series that focuses on the country’s top five causes of death and how we can drive down rates of these illnesses. Tomorrow’s piece will explore the third leading cause of death: Alzheimer’s. You can also read our first article on <a href="https://theconversation.com/how-australians-die-cause-1-heart-diseases-and-stroke-57423">heart diseases and stroke</a>.</em></p>
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<p>Described as <a href="http://www.amazon.com/The-Emperor-All-Maladies-Biography/dp/1439170916">“The Emperor of All Maladies”</a> by Pulitzer Prize-winning author and researcher <a href="http://authors.simonandschuster.com/Siddhartha-Mukherjee/49784674">Siddartha Mukherjee</a>, cancer is often seen as a modern disease. But scientists have found evidence of it in <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3003131/">dinosaur fossils</a> and human cases appear in literature spanning four millennia. </p>
<p>The Egyptian physician Imhotep <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3997531/">vividly described advanced breast cancer</a> in 2600 BC as “<a href="https://books.google.com.au/books?id=hgx0sJvphNkC&pg=PA40&lpg=PA40&dq=cool+hard+dense+as+hemat+fruit&source=bl&ots=1FQSiRjT-C&sig=ZgjwyopC7l-WgIh-xJF1s6IVGfM&hl=en&sa=X&ved=0ahUKEwjZ_emD3pLNAhVJo5QKHV1JBYkQ6AEIHDAA#v=onepage&q=cool%20hard%20dense%20as%20hemat%20fruit&f=false">a bulging mass in the breast</a>”: cool, hard and spreading beneath the skin. Under the section “Therapy”, Imhotep solemnly recorded: “<a href="https://books.google.com.au/books?id=hgx0sJvphNkC&pg=PA40&lpg=PA40&dq=cool+hard+dense+as+hemat+fruit&source=bl&ots=1FQSiRjT-C&sig=ZgjwyopC7l-WgIh-xJF1s6IVGfM&hl=en&sa=X&ved=0ahUKEwjZ_emD3pLNAhVJo5QKHV1JBYkQ6AEIHDAA#v=onepage&q=%22there%20is%20none%22&f=false">There is none.</a>”</p>
<p>An early modern <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2128854/pdf/medcht00065-0003.pdf">publication on cancer comes from 1818</a>. Written by physician George Wagstaff, it includes a number of gruesome case studies such as that of “fungus haematodes”, or blood fungus in the lungs. </p>
<p>Since then, more than three million scientific papers have been published on the subject, 159,000 of them in 2015 alone.</p>
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<p>Between 1968 and 2013 <a href="http://www.aihw.gov.au/acim-books/">cancer deaths in Australia</a> increased from 17,032 to 44,308, a rise of 160%. However, taking into account the increase in population (94%) and the increase in average age (34%) over the same period, there has been a decline in the age-standardised cancer death rate overall in Australia. The chance of a cancer death before the age of 75 in 1968 was 12.8%. This has fallen to 9.4% in 2013.</p>
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<p>Cancer is made up of around 200 distinct illnesses united by the uncontrolled growth of human cells. The diversity of mechanisms by which different cancer types both grow and evade treatment means that many separate breakthroughs will be required to combat all cancers.</p>
<p>Currently, seven cancer types are listed in the <a href="http://www.abs.gov.au/ausstats/abs@.nsf/Lookup/by%20Subject/3303.0%7E2014%7EMain%20Features%7ELeading%20Causes%20of%20Death%7E10001">top 20 causes of death</a> in Australia. These are cancers of the lung, blood and lymph, bowel, prostate, breast, pancreas and skin.</p>
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<figure><figcaption>The How Australians Die series has combined all cancer deaths to make them the second leading cause of death after heart diseases and stroke. Alzheimer’s is number 3, respiratory diseases, number 4 and diabetes, number 5.</figcaption></figure>
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<h2>Lung cancer</h2>
<p>This is the number one cancer killer, ranking number four in overall causes of death. <a href="http://www.aihw.gov.au/WorkArea/DownloadAsset.aspx?id=60129555176">Most (80%) lung cancers are still attributable to tobacco smoking</a>, either directly or through passive smoking. Australia is leading the world in reducing smoking rates and fewer than 13% of <a href="http://www.tobaccoinaustralia.org.au/chapter-1-prevalence/1-3-prevalence-of-smoking-adults">Australian adults now smoke</a>, with fewer lung cancer cases as a result.</p>
<p>Sadly, lung cancer survival remains poor due in part to late detection. Less than 15% of people are still alive five years after diagnosis although new <a href="http://bmcpulmmed.biomedcentral.com/articles/10.1186/1471-2466-12-77">immunotherapy treatments</a> that help the immune system destroy cancer cells are prolonging survival for some patients. </p>
<p>Also, <a href="http://www.ncbi.nlm.nih.gov/pubmed/26763803">trials screening people at high risk</a>, particularly smokers, using chest CT scans are showing promise in catching the disease earlier and at a more curable stage.</p>
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<img alt="" src="https://images.theconversation.com/files/122435/original/image-20160513-27184-hjnzfw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/122435/original/image-20160513-27184-hjnzfw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=402&fit=crop&dpr=1 600w, https://images.theconversation.com/files/122435/original/image-20160513-27184-hjnzfw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=402&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/122435/original/image-20160513-27184-hjnzfw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=402&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/122435/original/image-20160513-27184-hjnzfw.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=505&fit=crop&dpr=1 754w, https://images.theconversation.com/files/122435/original/image-20160513-27184-hjnzfw.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=505&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/122435/original/image-20160513-27184-hjnzfw.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=505&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Most lung cancers are attributable to tobacco smoke.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/kylesatori/4650255057/in/photolist-85VLPk-6zcf1r-pCJrZ7-8P8iX-7jzoZ8-55ZgRD-bmiUwX-caLjtm-bV7KzN-8ZDpWJ-6hzGDX-nzVzhZ-6hzGKD-nu9cJ-5THWVF-csEp2u-pcbutn-cx35sj-GGW4-RmCwd-ouvRb4-6txjrq-nk8yxk-cQjrzu-6LkHp3-fhGr8v-qYBCkY-9E8Ros-DcrJk-cepTSU-cPCph5-9P6oma-a7q6zT-Btw3To-9sRHm4-64L1oM-8JBeip-7Xutv2-dpHHp4-ptDVJf-jtjAc-aaR9Af-jtjAb-6TPX8J-7jz8aF-5FDUvv-dm6vt-67K1Ww-a8Bf8a-9vhUju">Bruno de Souza Leão/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
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<h2>Blood and lymph cancer (including leukaemia)</h2>
<p>Cancers of the lymph glands (lymphomas) affect the body’s infection fighting mechanism and come in two types: Hodgkin and Non Hodgkin lymphoma. Blood cancers are called leukaemia and classified as either acute (fast growing) or chronic (slow growing). </p>
<p>Combined, these cancers are referred to as haematological cancers and they caused 4,275 deaths in Australia in 2013 (made up mostly of lymphoma and leukaemia caused deaths). For each, there are <a href="http://www.nhs.uk/ipgmedia/national/Lymphoma%20Association/Assets/Leukaemiaandlymphoma-thedifference.pdf">sub types with different features</a>, treatments and survival rates. Little is known about the causes of these cancers but survival is improving for many types.</p>
<h2>Large bowel cancer</h2>
<p>In 2014, 4,169 people died of bowel cancer (0.9% chance of death before age 75) compared to 2,500 in 1968 (1.9%). These cancers can often be treated successfully if found early through faecal blood testing such as in the <a href="http://www.cancerscreening.gov.au/bowel">National Bowel Cancer Screening Program</a>. </p>
<p>However, since the program began in 2006, <a href="http://www.cancerscreening.gov.au/internet/screening/publishing.nsf/Content/nbcsp-fact-sheet">only 40% of those invited have done the test</a>. Despite men being diagnosed more, at a later stage and being more likely to die from bowel cancer, they are less likely than women to participate.</p>
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<h2>Prostate cancer</h2>
<p>In 2014, 3,102 Australian men died of prostate cancer, up from 963 in 1968. Diagnosis and death are rare for those under 50 but the disease becomes increasingly common in older men with over half of prostate cancer deaths occurring after 80. Causes are unknown making preventative options hard to identify.</p>
<p>Although diagnosis is common, only one in six men who are diagnosed die of prostate cancer. The five year <a href="http://www.aihw.gov.au/WorkArea/DownloadAsset.aspx?id=60129545133">survival rates exceed 90%</a>, giving prostate cancer the reputation of being a disease one dies with rather than from. However the large number of cases, particularly in much older men, mean it remains a major cancer killer.</p>
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<img alt="" src="https://images.theconversation.com/files/125248/original/image-20160605-11620-1340d2z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/125248/original/image-20160605-11620-1340d2z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=719&fit=crop&dpr=1 600w, https://images.theconversation.com/files/125248/original/image-20160605-11620-1340d2z.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=719&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/125248/original/image-20160605-11620-1340d2z.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=719&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/125248/original/image-20160605-11620-1340d2z.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=904&fit=crop&dpr=1 754w, https://images.theconversation.com/files/125248/original/image-20160605-11620-1340d2z.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=904&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/125248/original/image-20160605-11620-1340d2z.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=904&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">More breast cancers are not being detected at a curable stage.</span>
<span class="attribution"><span class="source">from shutterstock.com</span></span>
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<p>Surgery and <a href="http://www.cancer.org.au/about-cancer/after-a-diagnosis/after-a-diagnosis-of-prostate-cancer.html">radiotherapy are the most common</a> treatments. Hormone therapy, recently combined at the beginning with chemotherapy, can often control more widespread disease for long periods. </p>
<h2>Breast cancer</h2>
<p>Perhaps the highest-profile cancer, progress in breast cancer has been strong. However, 2,844 Australians, including about 30 men, still died of breast cancer in 2014 in Australia. </p>
<p>Breast cancer is now divided into <a href="https://www.bcna.org.au/understanding-breast-cancer/types-of-breast-cancer/">different sub-types</a>, each with its own behaviour. Understanding this has allowed more personalised therapy for many patients, which has improved treatment outcomes.</p>
<p>Mammographic screening has <a href="http://www.abc.net.au/health/features/stories/2014/03/14/3962769.htm">attracted some controversy</a> because of possible over-diagnosis. But with participation rates well above 50%, and more cancers being detected at more curable stages, it has likely contributed to the rise of five year survivals to 90%.</p>
<h2>Pancreatic cancer</h2>
<p>Little progress has been made in pancreatic cancer that took 2,547 Australians in 2014, compared to <a href="http://www.aihw.gov.au/acim-books/">797 in 1968</a>. Smoking, obesity and some pesticides can contribute to pancreatic cancer risk. </p>
<p>An absence of signs and tests make early detection uncommon and little progress has been made in identifying important drivers of pancreatic cancer growth. As diagnosis often occurs at an advanced stage and focused treatments are lacking, outcomes are poor with a <a href="http://www.cancer.org.au/about-cancer/types-of-cancer/pancreatic-cancer.html">five year survival rate of only 5%</a>.</p>
<h2>Skin cancers</h2>
<figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/125249/original/image-20160605-11620-re3k4r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/125249/original/image-20160605-11620-re3k4r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=722&fit=crop&dpr=1 600w, https://images.theconversation.com/files/125249/original/image-20160605-11620-re3k4r.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=722&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/125249/original/image-20160605-11620-re3k4r.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=722&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/125249/original/image-20160605-11620-re3k4r.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=908&fit=crop&dpr=1 754w, https://images.theconversation.com/files/125249/original/image-20160605-11620-re3k4r.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=908&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/125249/original/image-20160605-11620-re3k4r.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=908&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Melanoma is the leading cause of skin cancer deaths.</span>
<span class="attribution"><span class="source">from shutterstock.com</span></span>
</figcaption>
</figure>
<p>Of the 2,067 skin cancer deaths, approximately 1,600 were due to melanoma while non-melanoma skin cancer (NMSC), a far more common but less lethal form, claimed the others in 2014. Excessive ultraviolet radiation from sunlight remains the main cause for both.</p>
<p>Recently, New Zealand surpassed Australia <a href="http://www.jidonline.org/article/S0022-202X%2816%2900488-7/pdf">as the number one skin cancer nation</a> in the world. Melanoma cases are falling in Australia, probably due to prevention efforts.</p>
<p>Generally, treatment of early stage disease is highly successful with a greater than 95% five year survival rate. Even for advanced melanoma, <a href="http://www.cancerresearch.org/cancer-immunotherapy/impacting-all-cancers/melanoma">new immunotherapy treatments are increasing survival times</a>.</p><img src="https://counter.theconversation.com/content/58063/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Terry Slevin works for Cancer Council WA and serves as a spokesperson for Cancer Council Australia. He has been an investigator on various cancer research projects funded by state and national research funding organisations.
</span></em></p><p class="fine-print"><em><span>Andrew Redfern receives funding from the Cancer Council WA and the Health Department of WA.</span></em></p>Currently, seven cancer types are listed in the top 20 causes of death in Australia. These are cancers of the lung, blood and lymph, bowel, prostate, breast, pancreas, skin and some childhood cancers.Terry Slevin, Adjunct Professor, School of Psychology and Speech Pathology, Curtin University; Education and Research Director, Cancer Council WA; Chair, Occupational and Environmental Cancer Committee, Cancer Council AustraliaAndrew Redfern, Senior Lecturer, The University of Western AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/513842015-12-07T02:03:51Z2015-12-07T02:03:51ZHealth Check: what does the UV Index mean?<figure><img src="https://images.theconversation.com/files/104564/original/image-20151207-22673-18hhkyj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The UV Index was created last century largely for North American and European conditions, which rarely reach the 'extreme' range. </span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/andyinnyc/2593475487/">Andy Cross/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span></figcaption></figure><p>Alongside the day’s high and low temperatures, weather reports generally contain a UV alert for a particular time. But what does it actually mean – and what should you do about it?</p>
<p>Ultraviolet light is a form of radiation invisible to the human eye. Ultraviolet wavelengths of sunlight are made up of UVB, which has shorter wavelengths (of 290 to 320 nanometres) and higher energy, and UVA, which has longer wavelengths (320 to 400 nm) and lower energy. </p>
<p>Both types of UV damage skin cells and both are thought to contribute to skin cancer. But UVB causes sunburn and UVA contributes more to ageing and penetrates deeper skin layers.</p>
<p>It is <a href="http://www.ncbi.nlm.nih.gov/pubmed/26437734">estimated</a> that 7,220 cases of melanoma – 63% of the total number – in Australia in 2010 and all of the 750,000-plus non-melanoma skin cancers were due to exposure to our high-UV climate.</p>
<p>The <a href="http://www.who.int/uv/en/">Ultra Violet Radiation Index</a> (UVI) has been around for more than 20 years and gives a measure of the intensity of the sun, using both UVA and UVB.</p>
<p>The World Health Organisation recommends protecting our skin from the sun when the UVI is 3 or higher. So the “alert” applies to the block of time the UVI is 3 or above though the course of any day.</p>
<p>UVI 1–2 is low, which generally means it’s safe to be outdoors unprotected. </p>
<p>Other classifications are moderate (3–5), high (6–7), very high (8–10) and extreme (11+). To some extent, the moderate to very high labels tell us little except that UV intensity is increasing. The most simple advice is that when the index is at 3 or higher, protect your skin. Hence the “alert”.</p>
<p>To illustrate, today in <a href="http://www.bom.gov.au/qld/uv/#state-table">Cairns</a> the alert period was 8.10am to 4.10 pm, with a UV Index peak of 13 and extreme levels between about 10am and 2pm. </p>
<p>In <a href="http://www.bom.gov.au/tas/uv/index.shtml">Hobart</a>, the UV alert ran from 8.50am to 5.10pm, with a peak of UVI 10 and not reaching the extreme range. </p>
<p><strong>UV forecast for Monday, December 7, 2015</strong></p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/104568/original/image-20151207-22706-1k8cj58.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/104568/original/image-20151207-22706-1k8cj58.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=660&fit=crop&dpr=1 600w, https://images.theconversation.com/files/104568/original/image-20151207-22706-1k8cj58.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=660&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/104568/original/image-20151207-22706-1k8cj58.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=660&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/104568/original/image-20151207-22706-1k8cj58.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=829&fit=crop&dpr=1 754w, https://images.theconversation.com/files/104568/original/image-20151207-22706-1k8cj58.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=829&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/104568/original/image-20151207-22706-1k8cj58.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=829&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
<span class="attribution"><a class="source" href="http://www.bom.gov.au/australia/uv/">Screen shot from the Bureau of Meteorology website.</a></span>
</figcaption>
</figure>
<p>The <a href="http://www.bom.gov.au/australia/uv/#statelist">Bureau of Meteorology</a> has live <a href="http://www.myuv.com.au/public-real-time-uv-meter/">UV meters</a> for more accurate, on-the-spot local readings around the country.</p>
<p>One challenge is that the UV Index was created last century largely for North American and European conditions. There the UVI rarely gets into the extreme range. </p>
<p>In Australia, we spend most of the summer with “extreme” UV conditions in the middle of the day. There are concerns that the effect of the term “extreme” wears off if it is the norm. This will be one of the points debated at the <a href="http://uvandskincancer2015.org/">International Conference</a> on UV and Skin Cancer Protection in Melbourne this week.</p>
<h2>What affects UV intensity?</h2>
<p>UV radiation is separate from the visible and infrared parts of the spectrum, so you can’t see or feel it. That means you can be at the cricket or the beach in summer at 5pm and feel hot but the UVI might be in the low range of 1 or 2. </p>
<p>Or you can be in the same place, in a cool breeze on a 22 degree summer’s day at 1pm and get seriously burned due to the extreme UV index. </p>
<p>Heavy storm clouds can reduce the UV Index enormously; thin passing cloud, not so much.</p>
<p>UV radiation reflects off many surfaces including concrete, water and snow. Indirect UV (refracted by the atmosphere) can burn even if you are in the shade of a beach umbrella. If you can see lots of sky – even if you are in a little shade – chances are you are getting a pretty big dose of UV.</p>
<p>But there is a lot around to help. Being indoors provides great UV protection, even near the window (most office window glass gives very good UV protection). </p>
<p>Summer clothing can vary from the crocheted bikini (not so good) to a close-knit cotton shirt and shorts or a flowing sundress. The fabric weave and coverage are the keys – and look for UPF50 (ultraviolet protection) ratings. The best thing about clothing is you can see exactly what is or is not protected.</p>
<p>Sunscreen is <a href="http://www.ncbi.nlm.nih.gov/pubmed/24417448">proven</a> effective to reduce skin cancer. But most of us do not use enough to reach the protection claimed on the label. </p>
<p>Shade cloth was originally invented for horticultural purposes and can be as low as an equivalent SPF of 3–4, but some offer more effective UV protection. </p>
<p>Likewise, a small-leaf sparse-canopy gum tree does not provide nearly the same shade protection as a big old Moreton Bay fig.</p>
<p>Finally, skin type is important. Those blessed with naturally dark skin (like Aboriginal people who have evolved in our climate) have inherited a lower skin cancer risk than those of us from northern European heritage with pale, easily burned and sun-sensitive outer casing. </p>
<p><em>Terry Slevin is the editor of <a href="http://www.publish.csiro.au/pid/7227.htm">Sun Skin and Health</a>, released by CSIRO Publishing.</em></p><img src="https://counter.theconversation.com/content/51384/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Terry Slevin works for Cancer Council WA. The Cancer Council sells a range of sun-protection products including sunscreens, the royalties of which fund cancer research, prevention and support programs.</span></em></p>Alongside the day’s high and low, weather reports generally contain a UV alert for a particular time. But what does it actually mean – and what should you do about it?Terry Slevin, Adjunct Professor, School of Psychology and Speech Pathology, Curtin University; Education and Research Director, Cancer Council WA; Chair, Occupational and Environmental Cancer Committee, Cancer Council AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/498882015-10-30T04:08:54Z2015-10-30T04:08:54ZConfused about your cancer risk from eating meat? Here’s what the figures mean<figure><img src="https://images.theconversation.com/files/100255/original/image-20151030-20167-1obvecl.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Methods of communicating relative risk to the public are often confusing.</span> <span class="attribution"><a class="source" href="https://www.flickr.com/photos/b-tal/163450213/in/photolist-frJ48-6jVDrj-a3eRUW-7o37h4-dF2kfy-xSKtM3-45cqRN-9btpV5-2aG48A-zDxYmj-weYd8-h4yNV6-cdx6N3-9bfGvL-5WksQ6-nGtSb-eoKTfj-bTci2-4nasi8-398sRb-D2Gaj-cvL8q1-gvMnZ-8uts1c-d48xXC-x2N2-MX2qn-8xyKpN-63UskT-6znZE-8CExD3-e1L6W4-c4Rw4G-dpHVtD-7jf2C5-nXMLQ-4vTpFL-FMNav-6LZ96M-6N51SL-7iNtsT-iqKpmj-72j5yj-dM5ip5-7rYJ5k-6M4hgW-d2LRVu-9bFkti-6N1iga-z78tQo">Brian Talbot/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span></figcaption></figure><p>In a <a href="https://www.iarc.fr/en/media-centre/pr/2015/pdfs/pr240_E.pdf">recent report</a> on processed meat and risk of bowel cancer, the International Agency for Research on Cancer (IARC) stated: </p>
<blockquote>
<p>Each 50 gram portion of processed meat eaten daily increases the risk of colorectal cancer by 18%. </p>
</blockquote>
<p>This method of communicating risk led to confusion and some <a href="http://www.theatlantic.com/health/archive/2015/10/why-is-the-world-health-organization-so-bad-at-communicating-cancer-risk/412468/">hostile reactions</a>. Scientists can explain risks of cancer and other diseases in several ways; some are easier to understand than others.</p>
<h2>Relative risk</h2>
<p>The IARC statement is based on a summary of many epidemiological studies assessing the relationship between meat consumption and bowel cancer, including a <a href="http://www.ncbi.nlm.nih.gov/pubmed/15342453">study by one of us</a>. </p>
<p>Epidemiology is the science of studying the distribution and determinants of disease in populations. At its heart lie comparisons of the frequency of disease for people exposed or not exposed to a particular substance, environmental condition or lifestyle. </p>
<p>In this case, IARC was comparing the risk of bowel cancer for people who eat 50 grams of processed meat per day with the risk for those who don’t eat processed meat at all. </p>
<p>The 18% increase means the risk of developing bowel cancer is 1.18 times higher for those who eat 50 grams of processed meat per day compared to those who eat none. The figure 1.18 is known as “relative risk”. </p>
<p>Put this way, the increase is quite small. By contrast, <a href="http://www.ncbi.nlm.nih.gov/pubmed/15880414">men who smoke cigarettes</a> have about 20 times the risk of developing lung cancer as men who do not smoke. Expressed as a percentage, the increase in risk due to smoking is 1,900%.</p>
<p>A potential problem with presenting relative risk in the format IARC uses is that many people will incorrectly conclude that if they ate processed meat, they had an 18% (almost one in five) chance of getting bowel cancer. Thus, they were misled.</p>
<p>Presenting relative risks to the public in any format is not very informative. A better way to communicate the effect of specific risk factors is to present what is known as the “absolute risk”.</p>
<h2>Absolute risk</h2>
<p>Australians fortunate enough to live to the age of 85 have an 8.2% chance of being diagnosed with bowel cancer over their lifetime; this is the “lifetime risk”.</p>
<p>If we assume that a quarter of the Australian population eats 50 grams per day of processed meat, then the lifetime risk for the three-quarters who eat no processed meat would be 7.9% (or about one in 13). For those who eat 50 grams per day, the lifetime risk would be 9.3% (or about one in 11). </p>
<iframe src="https://charts.datawrapper.de/TS2hV/index.html" frameborder="0" allowtransparency="true" allowfullscreen="allowfullscreen" webkitallowfullscreen="webkitallowfullscreen" mozallowfullscreen="mozallowfullscreen" oallowfullscreen="oallowfullscreen" msallowfullscreen="msallowfullscreen" width="100%" height="400"></iframe>
<p>Although our estimate that one-quarter of the population eat 50 grams of processed meat daily is not likely to be correct, changing this proportion does not have much effect on the two absolute risks.</p>
<p>Of course, this naive calculation assumes everything else is equal; that people who eat processed meat differ in no other ways that affect risk of bowel cancer from those who do not.</p>
<p>But we know many factors contribute to risk of bowel cancer – being overweight, alcohol consumption, being physically inactive and family history, to name a few. With so many variables driving risk, it is clear no two people are likely to have exactly the same risk profile. </p>
<p>Cancer Research United Kingdom <a href="http://scienceblog.cancerresearchuk.org/2015/10/26/processed-meat-and-cancer-what-you-need-to-know/">presented the risks</a> in this way. </p>
<blockquote>
<p>Out of every 1,000 people in the UK, about 61 will develop bowel cancer at some point in their lives. Those who eat the lowest amount of processed meat are likely to have a lower lifetime risk than the rest of the population (about 56 cases per 1,000 low meat-eaters).</p>
</blockquote>
<p>If you only expect to live to 65, your chance of getting bowel cancer is 2.9% if you don’t eat processed meat and 3.4% if you eat 50 grams each day. Of course, if you indulge more, the risk increases, but to similar proportions for each additional 50 grams per day.</p>
<p>Absolute risks allow people to personalise the effects and to better compare them. Yes, calculating absolute risk requires a strong assumption that there are no other differences between people who are exposed and not exposed. But we still believe that being able to compare absolute risks is more informative and less likely to mislead than relative risks.</p>
<h2>Population attributable fraction</h2>
<p>Another useful way of communicating the burden of cancer due to a risk factor is to calculate what is known as the population attributable fraction – that is, the fraction of cancer that is due to the risk factor. </p>
<p>Researchers <a href="http://www.ncbi.nlm.nih.gov/pubmed/26437727">recently estimated</a> that 18% of bowel cancers in Australia could be attributed to consumption of red and processed meat (they did not have data to allow them to separate the effects of processed and red meat). This equated to about 2,600 cases in 2010.</p>
<p>The increase in risk due to red and processed meat is small, but together they account for many cases because Australians eat a lot of meat.</p>
<p>A lot of public money, via taxes or donated funds to cancer organisations, is invested in research. There is a moral imperative to report the findings of such research, but rarely is one study definitive. </p>
<p>So major reviews by IARC are vital to bring together the best assessment of the evidence about what does and does not contribute to cancer risk. And people want to know. </p>
<p>The best cancer is the one you never get. Given we know <a href="http://www.ncbi.nlm.nih.gov/pubmed/26437735">the cause of about one-third of cancers in Australia</a> (smoking, alcohol, lack of exercise and nutrition factors), it is not unreasonable to give the best available information to people about what we know. </p>
<p>But clearly we have a way to go in better communicating what these risks really mean and how people can use this information in their daily choices. </p>
<p>Luckily, decades of solid evidence underpins some pretty simple advice to stack the cancer odds in your favour. For most people:</p>
<p>Do more: physical activity, eating fruit and vegetables</p>
<p>Do less: drink alcohol, eat high-calorie food, processed and probably red meat, expose skin to intense sunlight</p>
<p>Don’t: smoke.</p><img src="https://counter.theconversation.com/content/49888/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Dallas English works for The University of Melbourne and the Cancer Council Victoria. He has received funding from the National Health and Medical Research Council for research on diet and cancer.</span></em></p><p class="fine-print"><em><span>Terry Slevin works for the Cancer Council Western Australia and has been involved in research on the communication of cancer risk. He is a member of the Public Health Association of Australia. </span></em></p>There are several ways scientists can explain risks of cancer and other diseases; some are easier to understand than others.Dallas English, Professor at University of Melbourne and Research Fellow, Cancer Council VictoriaTerry Slevin, Adjunct Professor, School of Psychology and Speech Pathology at Curtin University. He is the Education and Research Director Cancer Council WA and Chair Occupational and Environmental Cancer Committee , Cancer Council AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/450892015-07-23T07:27:57Z2015-07-23T07:27:57ZPromising prognosis as cancer deaths continue to fall<figure><img src="https://images.theconversation.com/files/89455/original/image-20150723-22852-onkjpq.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Overall cancer deaths continue to fall, but some cancers are being left behind.</span> <span class="attribution"><span class="source">woman with cancer, from shutterstock.com</span></span></figcaption></figure><p>The rate of Australians dying from cancer is on a steady, downhill trajectory, thanks to powerful advances made in prevention, diagnosis and treatment of the disease. New data from the<a href="http://www.aihw.gov.au/cancer/mortality-trends-projections/"> Australian Institute of Health and Welfare</a> shows a promising outlook for those diagnosed with cancer.</p>
<p>Deaths from all cancers combined fell from 199 per 100,000 people in 1968, to 167 per 100,000 in 2012 - a decline of 2.6 deaths per 100,000 people per year.</p>
<p>“This confirms that we are steadily making improvements in most cancers, in terms of survival,” said Professor Timothy Hughes, Cancer Theme Leader at SAHMRI.</p>
<p>“And it’s coming from better prevention, better screening and better therapy.” </p>
<p>The downward cancer mortality rate was higher for males than females. Male deaths decreased by 4.1 per 100,000 per year, between 1995 and 2012, compared to 1.8 deaths per 100,000 females per year.</p>
<p>One reason is the base rate of cancer deaths in women was lower than that of men, as men are generally more likely to be diagnosed with cancer than women.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/89411/original/image-20150723-22836-v54j6m.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/89411/original/image-20150723-22836-v54j6m.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/89411/original/image-20150723-22836-v54j6m.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=401&fit=crop&dpr=1 600w, https://images.theconversation.com/files/89411/original/image-20150723-22836-v54j6m.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=401&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/89411/original/image-20150723-22836-v54j6m.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=401&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/89411/original/image-20150723-22836-v54j6m.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=504&fit=crop&dpr=1 754w, https://images.theconversation.com/files/89411/original/image-20150723-22836-v54j6m.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=504&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/89411/original/image-20150723-22836-v54j6m.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=504&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">AIHW cancer codes can be viewed on their website - the codes listed in the appendix depict rare cancers.</span>
<span class="attribution"><a class="source" href="http://www.aihw.gov.au/cancer/mortality-trends-projections/">AIHW National Mortality Database, projected 2013 to 2025</a></span>
</figcaption>
</figure>
<p>Education and Research Director at the Cancer Council WA, Terry Slevin, said the declining trend was “significant”. But he added projection estimates may in some cases be conservative, arguing successful efforts in prevention of certain cancers would see their mortality rates driven down even further than the report’s figures.</p>
<p>He said lung cancer - the <a href="http://canceraustralia.gov.au/affected-cancer/cancer-types/lung-cancer/lung-cancer-statistics">most common cause</a> of cancer death in Australia - was one example where anti-smoking campaigns would contribute to mortality rates declining from 42.4 male deaths per 100,000 in 2013 to 33 in 2015.</p>
<p>“Another example is colorectal (bowel) cancer. While they’ve projected a substantial reduction in regards to mortality in men, their projection of the reduction in women is far more modest. </p>
<p>"If we can boost their participation rate in the National Bowel Screening Program, which is currently lower than it should be, I think we can see those figures driven down,” he said.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/89413/original/image-20150723-22816-1vcsr3i.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/89413/original/image-20150723-22816-1vcsr3i.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/89413/original/image-20150723-22816-1vcsr3i.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=394&fit=crop&dpr=1 600w, https://images.theconversation.com/files/89413/original/image-20150723-22816-1vcsr3i.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=394&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/89413/original/image-20150723-22816-1vcsr3i.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=394&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/89413/original/image-20150723-22816-1vcsr3i.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=495&fit=crop&dpr=1 754w, https://images.theconversation.com/files/89413/original/image-20150723-22816-1vcsr3i.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=495&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/89413/original/image-20150723-22816-1vcsr3i.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=495&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">AIHW cancer codes can be viewed on their website - the codes listed in the appendix depict rare cancers.</span>
<span class="attribution"><a class="source" href="http://www.aihw.gov.au/cancer/mortality-trends-projections/">AIHW National Mortality Database, projected 2013 to 2025</a></span>
</figcaption>
</figure>
<p>While the rate has dropped, a rise in population levels and ageing has caused, and will cause, the total number of cancer deaths to rise. </p>
<p>In addition to this, Ian Olver, Chair of Translational Cancer Research at the University of South Australia said changing risk factors for cancer, such as obesity, could lead to even further increases in cancer numbers.</p>
<p>Between 2012 and 2025, the total number of deaths from cancer is predicted to increase from an estimated 25,580 to 32,010 among males, and from 19,450 to 24,250 among females. The numbers will undoubtedly put further strain on health services.</p>
<p>“We’re going to have more people living with the disease as a chronic illness as more people are diagnosed with cancer but fewer die from it. So it’s not only the acute cost of treating cancer, it’s the cost of maintaining services for an increasing number of people who will survive longer with consequences that could be both psychological and physical,” said Ian Olver.</p>
<p>And although overall death rates are falling, the prognosis for some cancers is not as positive. Mortality rates for liver and prostate cancer, for instance, are projected to rise.</p>
<p>Liver cancer deaths were at 8.5 per 100,000 males in 2013 and 3.5 per 100,000 females. The report projects this will increase to 11.3 males in 2015 and 4.7 females.</p>
<p>And the prognosis for ovarian cancer mortality will decline only marginally - from 6.9 per 100,000 women in 2013, to 6.5 in 2025.</p>
<p>“I think there’s been increasing resources put into those cancers but there are specific reasons why they are challenging. In the case of ovarian cancer, it’s proved very difficult to identify early disease because it tends to spread in the early stage when it’s not terribly symptomatic and symptoms are not specific,” said Professor Hughes.</p>
<p>“It’s cause for reassurance that the things we’re doing are giving us steady improvements but some cancers are being left behind and need to be focused on.”</p><img src="https://counter.theconversation.com/content/45089/count.gif" alt="The Conversation" width="1" height="1" />
The rate of Australians dying from cancer is on a steady, downhill trajectory, thanks to powerful advances made in prevention, diagnosis and treatment of the disease.Sasha Petrova, Section Editor: EducationLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/418852015-05-17T20:05:17Z2015-05-17T20:05:17ZWorkers exposed to cancer-causing agents deserve compensation<figure><img src="https://images.theconversation.com/files/81799/original/image-20150515-8712-1gqkok2.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">People with skin cancers due to outdoor work receive around 15% of the total compensation paid.</span> <span class="attribution"><a class="source" href="http://www.shutterstock.com/pic-71418340/stock-photo-floor-tile-installation.html?src=lzKlP_h40fodOT57vfJnrA-1-97">sixninepixels/Flickr</a></span></figcaption></figure><p>Unlike workplace accidents, where injuries can be relatively quickly assessed and compensation awarded, it can take years or many decades before work-related cancers are diagnosed. </p>
<p>There is no doubt some exposures in the past have left workers with a cancer diagnosis that would not have otherwise occurred. Sometimes that happened before the link between the exposure and cancer was clearly understood, such as the early asbestos miners. </p>
<p>Since modern occupational health and safety legislation <a href="http://regnet.anu.edu.au/content/overview-work-health-and-safety-regulation-australia">came into play</a> in Australia in the 1970s and early 80s, exposures have included people working in the sun and people working in smokey bars and clubs. </p>
<p>To count the recent cost of cancer at work, we gathered data from Safework Australia spanning the 12 years to 2012. Our report, <a href="http://www.cancer.org.au/content/pdf/News/MediaReleases/2015/web%20%20Occupational%20report.pdf">released today</a>, shows 4,745 Aussies received a compensation payout for a cancer that was, at least in part, caused by an occupational exposure. This totalled A$360 million over the 12 years. </p>
<p>Sun exposure contributing to skin cancer was one of two big-ticket items. More than half (53%) of the claims related to neoplasams (another term for cancer, melanoma and non-melanoma skin cancers) of the skin of one kind or another. People with skin cancers due to outdoor work attracted 15% of the funds paid.</p>
<p>The other was asbestos: about three-quarters of the A$360 million has been paid to people with mesothelioma. </p>
<p>These sound like big numbers until we consider that the <a href="http://www.ncbi.nlm.nih.gov/pubmed/16800196">best estimates</a> suggest about 5,000 cancer cases each year (about 4,400 of whom are men) occur as a result of some kind of occupational exposure. That means less than 10% of the cancer cases suspected to be linked to work exposures manage to attract compensation. </p>
<h2>Why so little compensation?</h2>
<p>Some, but not all cancers, have clear causes. Mesothelioma, for instance, is unequivocally linked to asbestos exposure. </p>
<p>Lung cancer can be caused by the individual’s smoking, or in non-smokers, it might be linked to exposures such as second-hand smoke at work, <a href="http://www.ncbi.nlm.nih.gov/pubmed/24272527">silica</a>, formaldehyde and asbestos (for every mesothelioma case caused by asbestos there are probably two additional lung cancer cases).</p>
<p>However, workers who smoked and had workplace exposure to other cancer-causing agents may not be getting or even seeking compensation.</p>
<p>Some occupational exposures happen outside work too, such as sun exposure. But compensation should be paid if there is some demonstrable “work-related injury” that contributed to the disease. </p>
<p>So the PE teacher – who is also a surf lifesaver and cricketer – can still seek compensation for her squamous cell carcinoma after running school sport for the first 15 years of her career without wearing a hat and sunscreen. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/81797/original/image-20150515-8719-1p3yixe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/81797/original/image-20150515-8719-1p3yixe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/81797/original/image-20150515-8719-1p3yixe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/81797/original/image-20150515-8719-1p3yixe.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/81797/original/image-20150515-8719-1p3yixe.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/81797/original/image-20150515-8719-1p3yixe.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/81797/original/image-20150515-8719-1p3yixe.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">We still have no clear record of how much asbestos is in public and private buildings and homes in Australia.</span>
<span class="attribution"><a class="source" href="http://www.shutterstock.com/pic-143004142/stock-photo-grey-waved-asbestos-roof.html?src=XSmS2aHcW36q6439FPUocg-2-146">Nadiia Korol/Shutterstock</a></span>
</figcaption>
</figure>
<p>There are, of course, the chemical exposures specific to some industries that most people immediately think of when considering this issue. Benzene, formaldehyde and nitrosamines are known carcinogens and <a href="http://www.ncbi.nlm.nih.gov/pubmed/24158310">can all be found</a> in some Australian workplaces. </p>
<p>Diesel is another important example. A <a href="http://www.ncbi.nlm.nih.gov/pubmed/25711950">recent study</a> estimated almost 14% of the Australians workforce had significant exposure to diesel exhaust. And almost 2% had high levels in their current jobs. </p>
<p>The truckie spending 50 hours a week or more in the cabin breathing the exhaust from his own rig and the traffic around him is increasing his lung cancer risk. So too is the underground miner using diesel-driven mine equipment, particularly if in a confined space. </p>
<p>Emission-reduction technology will help. But transport workers of the past need to know they carry their previous exposure as a possible contributor to any future lung cancer. They carry that risk to a far greater extent than any routine commuter. </p>
<p>Painters and plumbers exposed to <a href="http://www.ncbi.nlm.nih.gov/pubmed/25018282">lead</a>, metal workers and electrical workers exposed to <a href="http://monographs.iarc.fr/ENG/Monographs/vol100C/mono100C-8.pdf">cadmium</a> and farmers and gardeners exposed to <a href="http://www.ncbi.nlm.nih.gov/pubmed/25801782">glyphosate</a> are all examples where products are still in use and personal protective equipment should be used. But it would be better would be to find other substances to serve the same function.</p>
<h2>Preventing work-related cancers</h2>
<p>When it comes to prevention, we’ve made some steady progress. Asbestos has been banned for decades and we’ve been banging on about SunSmart for more than 30 years. But in both cases we are not out of the woods.</p>
<p>We still have no clear record of how much asbestos is in public and private buildings and homes in Australia. Those working in construction, maintenance, renovation or refit do not have confidence in identifying asbestos. Nor do they have a clear diagram explaining where they might come across it in the work they do.</p>
<p>And there are still too many employers who have staff regularly working outdoors who do not have clear <a href="http://www.ncbi.nlm.nih.gov/pubmed/24270927">sun protection policies</a>.</p>
<p>For people who are diagnosed with cancers and who have a work history of being exposed to carcinogens, we need a better mechanism to identify the connection and explore proper compensation.</p>
<p>For the current and future generations of workers, we need to keep improving conditions to cut out as much exposure to cancer-causing agents as is humanly possible. Employers should be aware of the specific risks they have in their industry and either find different ways to tackle the task or, if that’s not viable, ensuring the risk is effectively removed or reduced. </p>
<p>Other groups also have important roles to play. Regulators need to keep on top of the best evidence on cancer-causing agents as they unfold. Doctors diagnosing cancer might also brush up on their work history recording skills. </p>
<p>Finally, workers also need to play their part by following health and safety procedures. The best cancer is the one we prevent.</p><img src="https://counter.theconversation.com/content/41885/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Terry Slevin receives funding from health and research funding agencies which finance health promotion programs (eg Departments of Health and Health Promotion Foundations) and public health research. He is affiliated with The Cancer Council WA and Cancer Council Australia and a member of the Public Health Association of Australia..</span></em></p>Unlike workplace accidents, where injuries can be relatively quickly assessed and compensation awarded, it can take years or many decades before work-related cancers are diagnosed.Terry Slevin, Adjunct Professor, School of Psychology and Speech Pathology at Curtin University. He is the Education and Research Director Cancer Council WA and Chair Occupational and Environmental Cancer Committee , Cancer Council AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/341432014-12-02T19:22:16Z2014-12-02T19:22:16ZHow to protect your skin while getting enough vitamin D<figure><img src="https://images.theconversation.com/files/66010/original/image-20141202-20560-twbg9s.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Aim to get a few minutes of summer sun each morning or afternoon.</span> <span class="attribution"><a class="source" href="http://www.shutterstock.com/pic-130244456/stock-photo-view-to-the-island.html?src=pp-same_model-130244426-ndolzVeR0gj_CCfpazE5Rw-2">ArTono/Shutterstock</a></span></figcaption></figure><p>It’s been more than 30 years since Sid Seagull first urged us to slip, slop and slap while out in the sun. But while we’ve <a href="http://www.ncbi.nlm.nih.gov/pubmed/24685358">made enormous</a> progress fighting skin cancer, melanomas are still the <a href="http://www.cancer.org.au/about-cancer/types-of-cancer/skin-cancer/melanoma.html">fourth most common</a> cancer in Australia and one of the most deadly. Add to the the huge burden of non-melanoma skin cancer.</p>
<p>From Cairns to Hobart, Brisbane to Perth and all points between, the UV Index will reach the “extreme” range most days this summer. </p>
<p>So how can you protect your skin while getting enough of the sunshine-derived vitamin D?</p>
<h2>Benefits and harms of ultraviolet radiation</h2>
<p>While limited dietary sources of vitamin D are available, exposure to ultraviolet radiation (UVR) is the most effective source of vitamin D for the majority of the world’s population.</p>
<p>Vitamin D deficiency is unquestionably linked to compromised bone health. While levels of evidence vary, it is also associated with <a href="http://www.ncbi.nlm.nih.gov/pubmed/24622671">a wide range</a> of other potential health problems. </p>
<p>On the other hand, excess UVR exposure is strongly linked to increasing risk of skin cancer. </p>
<p>To confuse the issue further, a <a href="http://www.ncbi.nlm.nih.gov/pubmed/?term=Liu+D+Fernandez+BO">recently published paper</a> suggested sun exposure might help reduce blood pressure and influence heart disease risk. But not through vitamin D. This research is still in its early days, but it may be that some of the benefits previously ascribed to vitamin D occur through other mechanisms related to sun exposure.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/65759/original/image-20141128-9779-14fn7cx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/65759/original/image-20141128-9779-14fn7cx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/65759/original/image-20141128-9779-14fn7cx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/65759/original/image-20141128-9779-14fn7cx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/65759/original/image-20141128-9779-14fn7cx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/65759/original/image-20141128-9779-14fn7cx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/65759/original/image-20141128-9779-14fn7cx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption"></span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/akasharkbow/14318524386">Getting enough vitamin D and protecting your skin is all about balance.</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc-sa/4.0/">CC BY-NC-SA</a></span>
</figcaption>
</figure>
<h2>How much is enough?</h2>
<p>Active debate continues about where cut points for deficiency and sufficiency should be drawn. </p>
<p>Serum levels of 25-hydroxy vitamin D (also called 25-OHD) are used to measure vitamin D adequacy. The Institutes of Medicine (IOM) <a href="http://www.iom.edu/Reports/2010/Dietary-Reference-Intakes-for-Calcium-and-Vitamin-D.aspx">2011 report</a> recommended deficiency be defined as 25-OHD less than 30 nanomoles per litre nmol/L and adequacy as 50 to 125 nmol/L. </p>
<p>The range of 30 to 50nmol/L is defined as “insufficient”, indicating some health risk to some but not all individuals. The report advises:</p>
<blockquote>
<p>Use of higher than appropriate cut-points for serum 25-OHD levels would be expected to artificially increase the estimates of the prevalence of vitamin D deficiency.</p>
</blockquote>
<p>The level of UVR exposure necessary to establish and maintain optimum levels of vitamin D varies across the world. It is influenced by geography, season, age, skin type and more. However, in <a href="http://www.bom.gov.au/australia/uv/">higher UVR locations</a> like ours, minimising UVR exposure during summer, and in particular in high UVR times of the day, remains a health priority.</p>
<h2>How many of us struggle to get enough?</h2>
<p>This is an age-old question. Of course, the answer depends on the definition of what is enough. The Australian Bureau of Statistics reported in April this year on 25 D measures taken from the <a href="http://www.abs.gov.au/ausstats/abs@.nsf/Lookup/4364.0.55.006Chapter2002011-12">National Health Survey in 2011/12</a> that:</p>
<blockquote>
<p>Just under one in four (23%), or four million adults, had a vitamin D deficiency, which comprised 17% with a mild deficiency, 6% with a moderate deficiency and less than 1% with a severe deficiency.</p>
</blockquote>
<p>The cut points and definitions are crucial. Australian researchers <a href="http://www.publish.csiro.au/pid/7227.htm">Robyn Lucas and Rachel Neale</a> propose a different presentation of those data: </p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/66016/original/image-20141202-20591-1lmrgn0.png?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/66016/original/image-20141202-20591-1lmrgn0.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/66016/original/image-20141202-20591-1lmrgn0.png?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=495&fit=crop&dpr=1 600w, https://images.theconversation.com/files/66016/original/image-20141202-20591-1lmrgn0.png?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=495&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/66016/original/image-20141202-20591-1lmrgn0.png?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=495&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/66016/original/image-20141202-20591-1lmrgn0.png?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=622&fit=crop&dpr=1 754w, https://images.theconversation.com/files/66016/original/image-20141202-20591-1lmrgn0.png?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=622&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/66016/original/image-20141202-20591-1lmrgn0.png?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=622&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption"></span>
</figcaption>
</figure>
<p>However these data are analysed, it is clear that about three-quarters of us have perfectly adequate levels of vitamin D. </p>
<p>By one interpretation, there are similar proportions of us who may have too much (which may contribute to some disease states) as have too little (which undoubtedly contributes to bone health problems).</p>
<p>As for the “vitamin D twilight zone” – levels of between 30 and 49nmol/L – Lucas and Neale question whether there are any adverse health effects at all. “It may be normal in mid to late winter. It may be a concern in late summer,” they say. </p>
<p>In May, 700,000 vitamin D were tests carried out in Australia. More than <a href="http://medicarestatistics.humanservices.gov.au/statistics/do.jsp?_PROGRAM=%2Fstatistics%2Fmbs_item_standard_report&DRILL=ag&group=66608&VAR=services&STAT=count&RPT_FMT=by+state&PTYPE=finyear&START_DT=201307&END_DT=201406">four million tests</a> were done in the last financial year. This <a href="http://medicarestatistics.humanservices.gov.au/statistics/do.jsp?_PROGRAM=/statistics/mbs_item_age_gender_report&VAR=benefit&STAT=count&PTYPE=finyear&START_DT=201307&END_DT=201406&RPT_FMT=by+state&GROUP=66608">cost A$145 million</a>, of which about A$98 million (two-thirds) was the cost of the test for women.</p>
<p>As a result of this burgeoning cost, changes were made to the Medicare Benefits Schedule, so only high-risk patients will get a rebate when they get vitamin D levels screened. Eligible patients include those with deeply pigmented skin, osteoporosis or those with chronic lack of sun exposure.</p>
<h2>What should we do?</h2>
<p>So what does make sense when it comes to sun exposure, skin cancer and vitamin D? The trick is, of course, getting the balance right and avoiding extremes, in one direction or the other.</p>
<p>Adjusting sun exposure according to the time of year and time of day is important. The UV Index will be in the extreme range in the middle of the day through most, if not all, of summer. So avoiding exposure for the few hours in the in the middle of summer days is smart. The World Health Organization recommends sun protection once the UV Index reaches or exceeds three.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/65744/original/image-20141127-9748-1cvtc5g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/65744/original/image-20141127-9748-1cvtc5g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/65744/original/image-20141127-9748-1cvtc5g.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/65744/original/image-20141127-9748-1cvtc5g.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/65744/original/image-20141127-9748-1cvtc5g.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/65744/original/image-20141127-9748-1cvtc5g.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/65744/original/image-20141127-9748-1cvtc5g.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Protect your skin during peak UV times.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/alexmartin81/7755295064">Alex Liivet/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>Skin type and geography are the other key factors: darker skin, a little more; lighter skin, a little less; further north, less exposure; further south, a little more.</p>
<p>People in special circumstances – who are immobile or infirm, or who routinely cover their skin for cultural or other reasons – should talk to their doctor about vitamin D.</p>
<p>Depending on where you live, five minutes of mid-morning or mid-afternoon sun two to three times a week – and certainly avoiding any sun burning – is a helpful rule. But it’s best to keep the head, face and neck protected as they get lots of sun and are at highest skin cancer risk.</p>
<p><em>Terry Slevin is editor of <a href="http://www.publish.csiro.au/pid/7227.htm">Sun, Skin and Health</a>, CSIRO Publishing.</em></p><img src="https://counter.theconversation.com/content/34143/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Terry Slevin is involved in Cancer Australia funded research project on Vitamin D . He is affiliated with the Cancer Council WA and Cancer Council Australia .</span></em></p>It’s been more than 30 years since Sid Seagull first urged us to slip, slop and slap while out in the sun. But while we’ve made enormous progress fighting skin cancer, melanomas are still the fourth most…Terry Slevin, Honorary Senior Lecturer in Public Health at Curtin University; Education & Research Director, Cancer Council WA; Chair of the Occupational and Environmental Cancer Committee, Cancer Council AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/246232014-03-21T03:32:25Z2014-03-21T03:32:25ZExplainer: what are cancer clusters?<figure><img src="https://images.theconversation.com/files/44373/original/wvpmy38n-1395296855.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">A cancer cluster generally features an unusually high number of the same type of cancer occurring in a group of people with a common exposure.</span> <span class="attribution"><a class="source" href="http://www.shutterstock.com/pic-174876020/stock-photo-interior-of-busy-modern-open-plan-office.html?src=geQShaL-RVH61pCEbfiqjg-1-46">Shutterstock</a></span></figcaption></figure><p>Most of us are <a href="http://demographics.treasury.gov.au/content/_download/australias_demographic_challenges/australias_demographic_challenges.pdf">living longer</a> and we are all expected to be <a href="http://www.smh.com.au/federal-politics/political-news/working-longer-retiring-stronger-20120208-1rf0g.html">working longer</a>. Because the likelihood of cancer increases as we age, we’re more likely to be diagnosed with cancer while still a member of the paid workforce. </p>
<p>That is equally true of our ageing workmates. An increasingly common phenomenon is that of a group of people – who might have been working in the same organisation for decades – will see their peers diagnosed with cancer around the same time.</p>
<p>Concerns that there may be a “cancer cluster” are sometimes raised when there is something unusual about the workplace: its location, the use of a certain types of equipment, old buildings that may contain known carcinogens such as asbestos, and so on.</p>
<p>Some of these factors seem to be at play in the most recent <a href="http://www.theaustralian.com.au/national-affairs/state-politics/mps-chook-house-cancer-fears/story-e6frgczx-1226858502405#mm-premium">suspected cancer cluster</a> at what is known as “the chook house” at the Victorian state Parliament. </p>
<p>Without knowing all the details it’s important to avoid making any specific comment on that case. But it raises an important issue: how do you differentiate between a “cancer cluster” and a normal pattern of cancer diagnoses?</p>
<p>A cancer cluster generally features an unusually high number of the same type of cancer occurring in a group of people with a common exposure – be it where they live, where they work or some other usually long-term exposure to an agent that has brought about the cancer.</p>
<p>The cancer cluster that attracted the most recent attention was the 2006 <a href="https://www.mja.com.au/journal/2007/187/3/there-will-be-no-more-legacy-toowong-breast-cancer-cluster">Brisbane ABC</a> case. Of the 550 female staff, ten women were diagnosed with invasive breast cancer between 1994 and 2006 – a six-fold increase over the number of cases that might have been expected. </p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/44375/original/n8yzty6t-1395297523.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/44375/original/n8yzty6t-1395297523.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=897&fit=crop&dpr=1 600w, https://images.theconversation.com/files/44375/original/n8yzty6t-1395297523.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=897&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/44375/original/n8yzty6t-1395297523.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=897&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/44375/original/n8yzty6t-1395297523.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1127&fit=crop&dpr=1 754w, https://images.theconversation.com/files/44375/original/n8yzty6t-1395297523.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1127&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/44375/original/n8yzty6t-1395297523.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1127&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Governments are still working out how to deal with the enormous (but as yet unquantified) amount of asbestos in our workplaces, homes and public buildings.</span>
<span class="attribution"><a class="source" href="http://www.shutterstock.com/pic-44275543/stock-photo-danger-asbestos-sign.html?src=pp-photo-97385540-UqQ5g9xEQJG7CQyVkm3h8Q-8">Shutterstock</a></span>
</figcaption>
</figure>
<p>The precise cause of those cancers remain uncertain, and the result being due to “chance” is still considered likely. The investigation did, however, lead to the building of a new ABC complex in Brisbane.</p>
<p>An earlier and now famous case was the <a href="http://www.safetyline.wa.gov.au/PDF/Transcripts/Wittenoom_Transcript.pdf">Wittenoom asbestos miners</a> and their families who have been diagnosed with a range of asbestos-related diseases, including <a href="http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/Mesothelioma">mesothelioma</a>, since the mine closed in the 1960s. This case helped confirm the now well-accepted link between exposure to asbestos and a number of respiratory diseases.</p>
<p>Uncertainty remains the most common outcome of cancer cluster investigations. A group in the United States examined the outcome of <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3408895/">428 cancer clusters</a> investigations over two decades in that country and found no real increase in cancer cases above what might have been expected in 87% of “clusters”. </p>
<p>The study found one cluster investigation where the genuine increase in cancer cases had an identifiable cause: ship builders living in South Carolina who were exposed to asbestos through their work at a naval shipyard. </p>
<p>Of the other 69 suspected clusters where a substantial increase in cancer rates were observed, the cause remained unclear. In the two remaining cases, there was some indication of an (inconclusive) association between an identified exposure – contaminated water and/or air due to industrial pollution – to leukaemia. </p>
<p>In Australia, potential <a href="http://www.nhmrc.gov.au/_files_nhmrc/publications/attachments/ps0006_statement_cancer_clusters.pdf">cancer cluster investigations</a> are conducted by epidemiologists, with involvement from occupational hygienists, statisticians and occupational physicians who are independent of the employer, and are often government employees or consulting academics.</p>
<figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/44376/original/hb3twspy-1395298116.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/44376/original/hb3twspy-1395298116.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/44376/original/hb3twspy-1395298116.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/44376/original/hb3twspy-1395298116.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/44376/original/hb3twspy-1395298116.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1130&fit=crop&dpr=1 754w, https://images.theconversation.com/files/44376/original/hb3twspy-1395298116.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1130&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/44376/original/hb3twspy-1395298116.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1130&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Cancer risk increases dramatically with age.</span>
<span class="attribution"><a class="source" href="http://www.shutterstock.com/pic-90609373/stock-photo-elderly-couple-posing-at-park.html?src=Toom37WZC8MCCnEsoDTKgw-1-124">Shutterstock</a></span>
</figcaption>
</figure>
<p>Half of all men and a third of all women in Australia are likely to have a <a href="http://www.cancer.org.au/about-cancer/what-is-cancer/facts-and-figures.html">cancer diagnosis by the age of 85</a>. </p>
<p>While common, cancer it is also <a href="http://www.ncbi.nlm.nih.gov/pubmed/7718649">the most feared</a> illness. It’s therefore important that an appropriate expert takes the time to listen carefully to the employees’ or residents’ concerns and any theories that might explain the phenomenon. </p>
<p>Cancer is not one disease but a category of disease that is made up of <a href="http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/Cancer_explained?open">over 200 different illnesses</a> with different causes, pathways and treatments. So if the suspected cluster involves lots of different types of cancer – some people effected by breast cancer, some by lung cancer, some bowel cancer and some leukaemias, for instance – then the workplace (or suburb or other exposure) is an unlikely culprit. </p>
<p>Likewise, if some of the people with cancer have been at that workplace or lived in that street (or had that exposure) for a short period, or had previous disease or risk factors that might explain the cancer, its unlikely to be a cluster.</p>
<p>After looking at the situation systematically, the employees’ or residents’ concerns may be allayed and the initial assessment concluded. </p>
<p>Of course, there may be <a href="http://www.ncbi.nlm.nih.gov/pubmed/24158310">legitimate grounds for concern</a>. For example, exposure to pesticides, solvents, wood dust, diesel exhaust and radiation are established carcinogens that occur in some workplaces. </p>
<p>In Australia, around <a href="http://www.ncbi.nlm.nih.gov/pubmed/16800196">5,000 cases of cancer a year</a> are a result of occupational exposures to things such as environmental tobacco smoke, UV radiation in addition to those mentioned above.</p>
<p>If health authorities have cause to proceed with a formal investigation and a known carcinogen is identified, employers or landlords should act immediately to remove or reduce exposure – waiting for the final results before taking action makes no sense. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/44377/original/b5tstfg9-1395298189.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/44377/original/b5tstfg9-1395298189.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/44377/original/b5tstfg9-1395298189.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/44377/original/b5tstfg9-1395298189.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/44377/original/b5tstfg9-1395298189.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/44377/original/b5tstfg9-1395298189.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/44377/original/b5tstfg9-1395298189.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Wood dust is a cancer-causing agent.</span>
<span class="attribution"><a class="source" href="http://www.shutterstock.com/pic-156981053/stock-photo-saw-mill-with-stack-of-wood.html?src=VKKwWlhbDHPsZoybVvJGLQ-1-15">Shutterstock</a></span>
</figcaption>
</figure>
<p>Finally, it’s important to keep things in perspective. While we don’t know for sure what causes about half of all cancers, lifestyle factors are probably far more likely to be contributing to <a href="http://www.cancer.org.au/preventing-cancer/">cancer risk</a> than where we work or where we live.</p>
<p>We can all reduce our <a href="http://www.iarc.fr/en/publications/books/wcr/wcr-order.php">cancer risk</a> by quitting or not taking up smoking, establishing and maintaining a healthy body weight, avoiding <a href="https://theconversation.com/sunscreen-skin-cancer-and-the-australian-summer-11633">excessive UV exposure</a> and excessive <a href="https://theconversation.com/health-check-does-alcohol-cause-cancer-22959">alcohol consumption</a>, being more physically active and <a href="http://www.dietandcancerreport.org/">eating healthy food</a>.</p>
<p>In broad terms Australia has a safe, well-managed environment with low levels of pollution by world standards. Constant effort is required to maintain and improve on that status. </p>
<p>And there is room for improvement. Like everything we do - even if we are doing okay, it makes sense to try and do even better. It’s a balancing act. But one that we will be increasingly required to face.</p><img src="https://counter.theconversation.com/content/24623/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Terry Slevin has been part of research grant proposals that have received grants form Cancer Australia, NHMRC and Healthway. He is an employee of Cancer Council Western Australia.</span></em></p>Most of us are living longer and we are all expected to be working longer. Because the likelihood of cancer increases as we age, we’re more likely to be diagnosed with cancer while still a member of the…Terry Slevin, Honorary Senior Lecturer in Public Health at Curtin University; Education & Research Director, Cancer Council WA; Chair of the Occupational and Environmental Cancer Committee, Cancer Council AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/229592014-02-10T03:32:19Z2014-02-10T03:32:19ZHealth Check: does alcohol cause cancer?<figure><img src="https://images.theconversation.com/files/41102/original/q22mztb5-1391995682.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Reduce your cancer risk by reducing your alcohol consumption. </span> <span class="attribution"><span class="source">V31S70/Flickr</span></span></figcaption></figure><p>Alcohol and cancer is a topic that arouses a lot of controversy: <a href="http://www.fare.org.au/education-resources/faqs-about-alcohol/">many Australians</a> like the odd drink but don’t want to make the connection to cancer, the world’s biggest killer. </p>
<p>The World Health Organisation’s new <a href="https://theconversation.com/cancer-the-worlds-biggest-killer-22762">World Cancer Report 2014</a> shows cancer is responsible for 8.2 million deaths in 2012. Around 340,000 of those deaths were the direct result of alcohol consumption.</p>
<p>The link between alcohol and cancer itself is not news. Way back in 1988, the WHO’s International Agency for Research on Cancer (IARC) <a href="http://monographs.iarc.fr/ENG/Monographs/vol44/volume44.pdf">concluded</a> that alcohol consumption was a group one carcinogen – a direct cause of cancer in humans.</p>
<p>What has evolved over the past 26 years is evidence showing alcohol caused more cancers than first thought. Alcohol has now <a href="http://www.dietandcancerreport.org/cancer_resource_center/downloads/Policy_Report.pdf">been conclusively shown</a> to cause breast cancer in women, bowel cancer in men, and cancers of the mouth, pharynx, larynx and oesophagus in everyone. There is <a href="http://www.dietandcancerreport.org/cancer_resource_center/downloads/Policy_Report.pdf">increasing evidence</a> that alcohol causes liver cancer in both women and men as well.</p>
<p>When it comes to cancer patterns, the IARC is the best of the best – the world’s leading cancer scientists, analysing huge population studies within an exhaustive evidentiary framework, to determine beyond doubt the causes of what is now the world’s biggest killer.</p>
<p>One of the most interesting aspects of the IARC’s work is that, despite the baseless catchphrase “everything gives you cancer”, the <a href="http://monographs.iarc.fr/ENG/Classification/">evidence shows</a> there are only a handful of proven cancer-causing agents: </p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/41103/original/zgzxw6j3-1391995865.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/41103/original/zgzxw6j3-1391995865.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=800&fit=crop&dpr=1 600w, https://images.theconversation.com/files/41103/original/zgzxw6j3-1391995865.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=800&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/41103/original/zgzxw6j3-1391995865.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=800&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/41103/original/zgzxw6j3-1391995865.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1005&fit=crop&dpr=1 754w, https://images.theconversation.com/files/41103/original/zgzxw6j3-1391995865.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1005&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/41103/original/zgzxw6j3-1391995865.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1005&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Even one or two drinks a day, every day over an extended period, can increase your cancer risk.</span>
<span class="attribution"><a class="source" href="http://www.flickr.com/photos/basheertome/2481406439/sizes/l/">basheertome/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<ul>
<li>tobacco</li>
<li>the combined effects of obesity, poor diet and physical inactivity</li>
<li>UV radiation</li>
<li>alcohol consumption</li>
<li>viral infections such as hepatitis and human papillomavirus</li>
<li>asbestos</li>
<li>salt</li>
<li>industrial chemicals, many of which have been banned in countries such as Australia.</li>
</ul>
<p>So in terms of risk, where does alcohol fit into the mix? </p>
<p>The new <a href="http://www.iarc.fr/en/publications/books/wcr/wcr-order.php">WHO report</a> shows around 4.2% of all global cancer deaths are directly attributed to alcohol consumption. In Australia, the percentage is likely to be higher (6.5% according to some analyses). The reason for that is simple: the average Australian drinks more than the average individual from most other countries.</p>
<p>The risk equation in terms of alcohol exposure is straightforward: the more you consume, the higher the risk. As with most carcinogens, it’s continuous, long-term exposure that does the most damage.</p>
<p>To put some context around the stats, even by the most conservative estimates, more Australians die each year from an alcohol-related cancer than from melanoma.</p>
<p>The good news is that although alcohol is a proven cause of cancer, you can reduce your cancer risk by reducing your alcohol consumption. It’s all a matter of informed choice.</p>
<p><a href="https://www.nhmrc.gov.au/your-health/alcohol-guidelines">Australian guidelines</a> recommend men and women consume no more than two standard alcoholic drinks on any given night to reduce the lifetime risk of alcohol-related harm. If you adhere to the guidelines, you will significantly reduce your cancer risk. But even one or two drinks a day, every day over an extended period, can <a href="http://jnci.oxfordjournals.org/content/101/5/281.2.full">increase your cancer risk</a> – especially for women.</p>
<p>So, what can regulators do? </p>
<p>Increased awareness would help. We’ve <a href="http://wiki.cancer.org.au/prevention/Position_statement_-_Consumer_information_and_labelling_of_alcohol">long made the case</a> for text warnings on alcohol products, just so people can make an informed choice about that extra drink. Warning labels would remind consumers of the risks whenever they’re exposed to the product. </p>
<p>Any potentially harmful product should carry a warning for the consumer. A box of matches does. And, while a misused match can cause death, we’re not losing more than 2,000 Australians each year to match-related fires and explosions, as we are to alcohol-related cancers. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/41101/original/n7jy6d3y-1391995462.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/41101/original/n7jy6d3y-1391995462.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/41101/original/n7jy6d3y-1391995462.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/41101/original/n7jy6d3y-1391995462.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/41101/original/n7jy6d3y-1391995462.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/41101/original/n7jy6d3y-1391995462.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/41101/original/n7jy6d3y-1391995462.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Warning: alcohol increases your risk of cancer.</span>
<span class="attribution"><a class="source" href="http://www.flickr.com/photos/stephenagregory/145630328/sizes/l/">StephenAGregory/Flickr</a></span>
</figcaption>
</figure>
<p>We’ve also <a href="http://www.cancer.org.au/content/pdf/ACDPA/110930-Final-ACDPA-PS-Alcohol-Taxation-position-paper.pdf">long made the case</a> that Australia’s alcohol taxation system is wrong. Harmful products should be taxed on a proportional basis, linked – where possible – to the agent that causes the harm. </p>
<p>With alcohol products, it’s the level of alcohol (and ethanol in the alcohol) that causes cancer, and most the other alcohol-related health problems. The tax component should be linked to the alcohol volume. </p>
<p>That way, as well deterring people from purchasing the most harmful alcohol products, governments have a revenue source to help pay for all the problems alcohol causes and to fund public education programs. (The fact that some wines are cheaper than bottled water says it all.)</p>
<p>Until we get better public policy settings to reduce the impact of cancer-related alcohol, it’s up to you to make an informed choice.</p><img src="https://counter.theconversation.com/content/22959/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Ian Olver receives funding from NHMRC. He is affiliated with Cancer Council Australia.</span></em></p>Alcohol and cancer is a topic that arouses a lot of controversy: many Australians like the odd drink but don’t want to make the connection to cancer, the world’s biggest killer. The World Health Organisation’s…Ian Olver, Clinical Professor of Oncology, Cancer Council AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/227622014-02-04T11:07:07Z2014-02-04T11:07:07ZCancer: the world’s biggest killer<figure><img src="https://images.theconversation.com/files/40620/original/kkfdm22t-1391494484.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Being obese increases your risk of a number of common cancers.</span> <span class="attribution"><span class="source">CGP Grey/Flickr</span></span></figcaption></figure><p>The <a href="http://www.iarc.fr/en/publications/books/wcr/wcr-order.php">World Cancer Report 2014</a>, the first global snapshot of cancer since 2008, shows the disease is now the world’s biggest killer. In 2012, there were 8.2 million cancer deaths and 14.1 million new cancer cases worldwide. Worse, those numbers are predicted to rise to 13 million deaths and 22 million cases per year by 2025. There is real reason for concern. </p>
<p>The report, released today, was produced by more than 250 experts from around the world and was edited and led by Australia’s own Professor Bernard Stewart from University of NSW, along with International Agency for Research on Cancer Director Dr Chris Wild. </p>
<p>Nothing can be discussed in health these days without considering cost. Those numbers are pretty frightening too. The report estimates that the cost of dealing with cancer around the world is in the vicinity of $US1.16 trillion. They suggest that equates to 2% of total global gross domestic product. </p>
<p>The numbers are mind-boggling. But what does it mean? What is the story in Australia and what do we do about it?</p>
<p>Well, it means cancer, along with cardiovascular disease, remains one of the biggest health challenges we face. Australia has the third-highest cancer rate in the world, behind Denmark and France. </p>
<p>Perversely, on a population level, a high rate of cancer could be considered a marker of a relatively healthy population. </p>
<p>Australia enjoys among the <a href="http://www.healthstats.nsw.gov.au/Indicator/bod_intlex/bod_intlex">greatest life expectancy</a> in the world. The longer we live, the greater our chance of being diagnosed with a degenerative disease such as cancer. That longevity is generally considered to be linked to improved safety (<a href="http://www.monash.edu.au/miri/research/reports/papers/fatals.html">fewer road deaths</a> and <a href="http://www.safeworkaustralia.gov.au/sites/SWA/about/Publications/Documents/451/Fatal_Occupational_Injuries_International_Comparison.pdf">deaths at work</a>), and improved management of big killers like <a href="http://www.aihw.gov.au/WorkArea/DownloadAsset.aspx?id=10737418530">cardiovascular disease</a> and infectious diseases. </p>
<p>And while there is always room for improvement, by any international comparison Australia enjoys a very high quality health care system. These things are all good news.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/40621/original/z2qzzb3q-1391494584.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/40621/original/z2qzzb3q-1391494584.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/40621/original/z2qzzb3q-1391494584.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/40621/original/z2qzzb3q-1391494584.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/40621/original/z2qzzb3q-1391494584.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/40621/original/z2qzzb3q-1391494584.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/40621/original/z2qzzb3q-1391494584.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The longer we live – the greater our chance of being diagnosed with a degenerative disease like cancer.</span>
<span class="attribution"><a class="source" href="http://www.flickr.com/photos/janramroth/1266257257/">Jan Ramroth/Flickr</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>The second factor in having high cancer rates is that we actively look for cancer in the form of cancer screening programs. The idea is obviously to find cancer early enough to successfully treat it. When we systematically go looking for more cancer (or most disease for that matter) we tend to find it. </p>
<p>So why are the number of deaths for cancer going up?</p>
<p>There are more people in Australia, and in the world. And there is still work to be done on the treatment front. Our treatments for breast cancer, prostate cancer and bowel cancer are getting better and more effective. We are not able to claim such success in relatively common cancers like lung cancer. And treatment is not so readily available in many countries.</p>
<p>But in Australia, like most developed countries, the <a href="http://www.aihw.gov.au/acim-books/">death rate from cancer</a> is actually coming down.</p>
<h2>Prevention</h2>
<p>The best cancer is the one you don’t get, so prevention remains vital.</p>
<p>We are making great progress on tobacco and <a href="http://www.cancercouncil.com.au/79110/reduce-risks/smoking-reduce-risks/tobacco-statistics/are-smoking-rates-declining/">Australia’s smoking rates</a> are down to about 15%. But that still means there are too many million Australians smoking. So the first port of call for cancer prevention is giving up the fags. </p>
<p>On the tobacco front, Australia’s success should be shared internationally where we have some responsibility to pass our experience to nations where smoking rates remain high or are even increasing. Government action such as <a href="https://theconversation.com/tobacco-tax-rise-will-help-smokers-butt-out-for-good-16608">increasing tax</a> on tobacco, <a href="https://theconversation.com/topics/plain-packaging">plain packaging</a> and supporting hard-hitting social marketing campaigns are the key.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/40622/original/d3zkhd28-1391494595.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/40622/original/d3zkhd28-1391494595.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=438&fit=crop&dpr=1 600w, https://images.theconversation.com/files/40622/original/d3zkhd28-1391494595.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=438&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/40622/original/d3zkhd28-1391494595.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=438&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/40622/original/d3zkhd28-1391494595.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=550&fit=crop&dpr=1 754w, https://images.theconversation.com/files/40622/original/d3zkhd28-1391494595.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=550&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/40622/original/d3zkhd28-1391494595.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=550&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Sun exposure and obesity increase the risk of cancer.</span>
<span class="attribution"><span class="source">Kyle May/Flikr</span>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
</figcaption>
</figure>
<p>For non-smokers, the most important way to reduce cancer risk is achieving or retaining a healthy weight – through healthy diet and being physically active. Healthy food and lots of movement are both thought to help <a href="http://www.dietandcancerreport.org/">reduce cancer risk</a>, although the detail on diet remains challenging. But there is no doubt being obese increases your risk of developing a number of common cancers. </p>
<p>We also need government action to make healthier choices easier choices. Reducing the out-of-control <a href="https://theconversation.com/topics/junk-food-advertising">marketing of unhealthy food</a>, particularly that aimed at kids, might be a useful step.</p>
<p>Being <a href="https://theconversation.com/sunscreen-skin-cancer-and-the-australian-summer-11633">SunSmart</a> and cutting down on the booze are other well-established cancer prevention strategies.</p>
<h2>International snapshot</h2>
<p>No-one should look at the World Cancer Report 2014 just through Australian eyes. </p>
<p>It is no surprise that there is an enormous gap between the haves and the have-nots. Less than 5% of the populations of Africa, Asia and Latin America are covered by formal cancer registries. So the data drawn upon for reports of this kind are sketchy for a big proportion of the world. </p>
<p>The data available suggests that while these folk report 60% of the world’s cancer cases, they account for 70% of the world’s cancer deaths. </p>
<p>It also shows that more than half the children diagnosed with cancer in Africa and Asia die as a result of the disease compared with less than 20% in the developed world.</p>
<p>We have a lot of knowledge and capacity to share. World Cancer Day is an initiative of the <a href="http://www.uicc.org/">Union for International Cancer Control</a> (UICC) made up of around 800 member cancer organisations from around the world. They rightly focus their efforts on a Robin Hood approach of taking (technologies and solutions) from the rich and trying to give (facilitate, communicate, support) to the poorer resourced parts of the world.</p>
<p>As Dr Margaret Chan wrote in the foreword of the WCR14:</p>
<blockquote>
<p>Many developing countries find themselves in the grip of cancers from two vastly different worlds. Those associated with the world of poverty, including infection–related cancers, are still common, while those associated with the world of plenty are increasingly prevalent, owing to the adoption of industrialised lifestyles, with increasing use of tobacco, consumption of alcohol and highly processed foods, and lack of physical activity.</p>
</blockquote>
<p>A report which aims to sum up the new information on cancer around the world over the past five years is going to have an enormous amount of vitally important material to battle cancer over the next five years. All involved should be proud of their effort. So now onto action! </p><img src="https://counter.theconversation.com/content/22762/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Terry Slevin has been part of research grant proposals that have received grants form Cancer Australia, NHMRC and Healthway. He is an employee of Cancer Council Western Australia.</span></em></p>The World Cancer Report 2014, the first global snapshot of cancer since 2008, shows the disease is now the world’s biggest killer. In 2012, there were 8.2 million cancer deaths and 14.1 million new cancer…Terry Slevin, Honorary Senior Lecturer in Public Health at Curtin University; Education & Research Director, Cancer Council WA; Chair of the Occupational and Environmental Cancer Committee, Cancer Council AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/213652014-01-06T03:30:23Z2014-01-06T03:30:23ZHealth Check: how harmful is social smoking?<figure><img src="https://images.theconversation.com/files/38483/original/frh5ctzz-1388969739.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Just over 15% of Australians smoke daily and a further 1.5% smoke each week.</span> <span class="attribution"><span class="source">Flickr/benessere</span></span></figcaption></figure><p>If you only light up when you’re drinking or out with friends, you probably don’t identify as a smoker or consider the health impact of the occasional fag. Social smokers don’t usually smoke every day but consume a low level of tobacco over a long period. </p>
<p>Thirty years ago, the tobacco industry <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2771192/">studied</a> social smokers because they wanted to promote the “social benefits” of smoking. They discovered many were motivated to achieve a certain image or wanted help relaxing and de-stressing. The companies tried to tap into this market, offering smaller pack sizes and promoting cigarettes which were claimed to be safer and non-habit forming; which of course was <a href="http://www.ncbi.nlm.nih.gov/pubmed/19589449">nonsense</a>.</p>
<p>Modern social smokers are typically younger, better educated and more affluent than other smokers and often smoke to <a href="http://www.ncbi.nlm.nih.gov/pubmed/12893622">gain acceptance</a> among their social group, rather than in response to a <a href="http://www.healtheducation.uci.edu/tobacco/socialsmoking.aspx">craving for nicotine</a>. </p>
<p>It’s difficult to know the percentage of smokers who currently fall into the social smoker category because this is group isn’t explicitly counted. But <a href="http://www.tobaccoinaustralia.org.au/1-3-prevalence-of-smoking-adults">among Australians</a> over the age of 14, 15.1% smoke daily, 1.5% weekly and 1.4% less-than weekly. It’s unclear whether rates of social smoking in Australia are changing, but <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2771192/">American figures</a> suggest social smoking is on the rise.</p>
<p>Although social smokers may feel less vulnerable to harm than heavier smokers, they are still likely to suffer from smoking-related respiratory disease, heart attack, stroke and cancer. Smoking as little as one to four cigarettes each day <a href="http://www.icanquit.com.au/health/your-health/irregular-smoking-social-or-binge">triples your risk</a> of heart disease and lung cancer.</p>
<p>With more than 60 known carcinogens in cigarette smoke, the campaign slogan that every cigarette is <a href="http://www.cdc.gov/TOBACCO/data_statistics/sgr/index.htm">doing you damage</a> is true: the more you smoke, the greater your risk. And although social smokers only smoke occasionally, they may indulge in binge smoking on those occasions. </p>
<p>Because nicotine is so addictive, social smokers can quickly become more regular, addicted smokers. Before long, they’re buying their own cigarettes, starting to smoke alone and wake in the morning craving a cigarette. </p>
<p>It is also very difficult for regular smokers to decrease consumption – to become a social smoker – because nicotine is so addictive. </p>
<h2>The solution? Quit completely</h2>
<p>When social smokers quit, they may avoid the withdrawal symptoms suffered by those addicted to nicotine. So the <a href="http://smokefree.gov/explore-quit-methods">quit techniques</a> for regular daily smokers may not apply. </p>
<p>Tobacco industry research has shown that social smokers tend to be more concerned than regular smokers about second-hand smoke affecting non-smokers and that these concerns could influence their <a href="http://www.ncbi.nlm.nih.gov/pubmed/19589449">smoking behaviour</a> and decision to quit. After all, there’s nothing social about second-hand smoke.</p>
<figure class="align-right ">
<img alt="" src="https://images.theconversation.com/files/38274/original/cmfwfncv-1387429337.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/38274/original/cmfwfncv-1387429337.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=901&fit=crop&dpr=1 600w, https://images.theconversation.com/files/38274/original/cmfwfncv-1387429337.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=901&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/38274/original/cmfwfncv-1387429337.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=901&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/38274/original/cmfwfncv-1387429337.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1133&fit=crop&dpr=1 754w, https://images.theconversation.com/files/38274/original/cmfwfncv-1387429337.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1133&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/38274/original/cmfwfncv-1387429337.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1133&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Social smokers can quickly become more regular, addicted smokers.</span>
<span class="attribution"><span class="source">4.D/ Flickr</span></span>
</figcaption>
</figure>
<p>If you are a social smoker wanting to quit, try enlisting friends to dissuade you from lighting up in social situations. If you smoke when you drink alcohol, cutting back on booze may also help. </p>
<p>When you quit smoking, some of the improvements commence within hours, but the reduction in the risk of <a href="http://www.quit.org.au/reasons-to-quit/health-benefits-of-quitting">serious disease</a> will take many years. </p>
<p>Within the first six hours, the heart rate decreases and blood pressure drops. Most of the nicotine is cleared in the first day. </p>
<p>With a week, the sense of taste and smell improve and lungs begin to clear. The symptoms of a cough and wheeze progressively improve over the first year. </p>
<p>After ten years, the risk of lung cancer is lower than if the individual had continued smoking and by 15 years the risk of heart attack and stroke returns to those of someone who has never smoked.</p><img src="https://counter.theconversation.com/content/21365/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Ian Olver receives funding from NHMRC. He is affiliated with Cancer Council Australia.</span></em></p>If you only light up when you’re drinking or out with friends, you probably don’t identify as a smoker or consider the health impact of the occasional fag. Social smokers don’t usually smoke every day…Ian Olver, Clinical Professor of Oncology, Cancer Council AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/158142013-08-06T20:14:39Z2013-08-06T20:14:39ZSix things you need to know about your vitamin D levels<figure><img src="https://images.theconversation.com/files/28142/original/mqxj7rpy-1374817267.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Even if sunscreen is applied very thickly, vitamin D production is reduced but not stopped.</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>Vitamin D has emerged as “the vitamin of the decade”, with a long and growing list of maladies supposedly caused through its absence or prevented through its bountiful supply. </p>
<p>But is there adequate evidence for the wonders claimed for vitamin D or are we getting a bit carried away? </p>
<p>Before you answer that, here are some common misconceptions about vitamin D that you should know about.</p>
<ol>
<li>Everybody knows their vitamin D level should be above …?</li>
</ol>
<p>It’s a fairly universal agreement that a blood concentration of 25-hydroxyvitamin D (the usual measure of vitamin D status) below 25 nanomoles/litre (nmol/L) should be considered a serious deficiency.</p>
<p>Anyone who is tested and returns results like that needs to talk to their doctor about proper management. But knowing what levels are sufficient is trickier. </p>
<p>In 2010, the <a href="http://www.iom.edu/Reports/2010/Dietary-Reference-Intakes-for-calcium-and-vitamin-D.aspx">Institute of Medicine</a> in the United States concluded that bone health is the only condition for which there’s an established causal association with vitamin D. They found:</p>
<blockquote>
<p>health benefits beyond bone health — benefits often reported in the media — were from studies that provided often mixed and inconclusive results and could not be considered reliable.</p>
</blockquote>
<p>So there’s clearly contention about how much is enough. A level of 50nmol/L is sufficient to optimise the bone health of the majority of the population. But other groups recommend 75nmol/L, <a href="http://www.vitamindcouncil.org/about-vitamin-d/testing-for-vitamin-d/">100nmol/L or higher</a> (note that US sites provide recommendations in nanograms per millilitre or ng/ml – multiply by 2.5 to convert to nmol/L). </p>
<ol>
<li>There’s a vitamin D deficiency epidemic in Australia. </li>
</ol>
<p>Actually, what is most clear is that there’s an epidemic of vitamin D testing in Australia – a <a href="http://www.ncbi.nlm.nih.gov/pubmed/23794593">94-fold</a> increase from 2000 to 2010. Costs to Medicare have gone from $1.3 million in 2000/2001 to <a href="https://www.medicareaustralia.gov.au/statistics/mbs_item.shtml">$140.5 million in 2012/2013.</a></p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/28143/original/7z8fjxg2-1374817455.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/28143/original/7z8fjxg2-1374817455.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=662&fit=crop&dpr=1 600w, https://images.theconversation.com/files/28143/original/7z8fjxg2-1374817455.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=662&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/28143/original/7z8fjxg2-1374817455.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=662&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/28143/original/7z8fjxg2-1374817455.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=832&fit=crop&dpr=1 754w, https://images.theconversation.com/files/28143/original/7z8fjxg2-1374817455.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=832&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/28143/original/7z8fjxg2-1374817455.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=832&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Rather than an epidemic of deficiency, there’s currently an epidemic of vitamin D testing in Australia.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<p>Some populations are clearly at risk of vitamin D deficiency. People who habitually cover their skin while in public for cultural or other reasons, for instance, and the immobile elderly who are rarely sun exposed. But the evidence of population-wide vitamin D deficiency is thin and unconvincing, at least in part because vitamin D tests are problematic and the desired level is hotly debated. </p>
<p>If an unreliable test is used and the “sufficient” bar is set too high and more people are tested, then vitamin D “deficiency” will seem more common.</p>
<ol>
<li><p>A vitamin D test gives a simple answer and is accurate and reliable. </p>
<p>This is definitely not so.</p></li>
</ol>
<p>If you take blood from one person and split it up into several samples and test these, you can get very different results between the samples. And it’s not just a little bit different. </p>
<p>A recent Australian study assessing the consistency and accuracy of <a href="http://www.ncbi.nlm.nih.gov/pubmed/21395958">vitamin D tests</a> found that between one-in-five and one-in-three participants were misclassified as “deficient”. The vitamin D test results for a single blood sample returned enormously different results depending on which type of test was used and where the sample was analysed.</p>
<p>Four samples (out of approximately 800) differed by more than 100nmol/L (that’s double the usual “sufficient” level of 50nmol/L) across two different tests, and 10% of the results differed by more than 50nmol/L. These are different measurements of the same sample!</p>
<p>Fortunately work is underway to improve this abysmal situation. A group of international agencies are developing a reference measurement procedure and laboratories will be able to assess the performance of their test against this new standard.</p>
<ol>
<li>Vitamin D is the elixir of life, which is sometimes presented as vitamin D deficiency will kill us all.</li>
</ol>
<p>Given the challenges of accurately measuring levels of this vitamin and the disagreement on where the goalposts are, doing good consistent research to determine the benefits and detriments of high or low vitamin D is pretty difficult. </p>
<p>There’s no doubt that severe vitamin D deficiency causes rickets in children, and an equivalent condition known as osteomalacia in adults. Old pictures of children with bowed legs or knock knees were often of children with rickets. </p>
<p>And there’s pretty good evidence that supplementation with vitamin D <em>and</em> calcium, in combination with weight-bearing exercise, can decrease the risks of fractures in the elderly. Particularly in people who have low levels of vitamain D or calcium (or both) before starting supplementation.</p>
<p>But most evidence for the other reported benefits of vitamin D comes from weak studies, and there’s little support from better studies. </p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/28145/original/nv87v5h5-1374817852.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/28145/original/nv87v5h5-1374817852.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/28145/original/nv87v5h5-1374817852.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/28145/original/nv87v5h5-1374817852.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/28145/original/nv87v5h5-1374817852.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/28145/original/nv87v5h5-1374817852.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/28145/original/nv87v5h5-1374817852.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">There’s good evidence that supplementation with vitamin D and calcium, in combination with weight-bearing exercise, can decrease the risks of fractures in the elderly.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
</figcaption>
</figure>
<ol>
<li>Given it is such good stuff, the higher my vitamin D level, the better.</li>
</ol>
<p>Vitamin D has traditionally been thought to be safe, requiring very high levels (greater than 400nmol/L) to reach toxicity. This toxicity cannot occur through sun exposure, but can through excessive supplementation. </p>
<p>But as we delve more into the vitamin D story, studies are <a href="http://www.ncbi.nlm.nih.gov/pubmed/23666975">reporting risks to health</a> at even modestly high levels, such as 80-100nmol/L. </p>
<p>The evidence is not yet strong (much like the evidence of vitamin D’s benefits) but this type of association is typical of many vitamins and nutrients, where both <a href="http://www.ncbi.nlm.nih.gov/pubmed/23609334">too little and too much are bad for you</a> . </p>
<ol>
<li>Sunscreen stops vitamin D production.</li>
</ol>
<p>The majority of vitamin D your body needs comes through exposure to the sun, specifically from shorter wavelength UVB radiation that is also the main cause of skin cancers. It may seem logical that if sunscreen stops the damaging UVB reaching sensitive skin cells, it will also stop vitamin D production by those same cells. </p>
<p>But even if sunscreen is applied very thickly, vitamin D production is reduced but not stopped. And, of course, who puts it on that thickly? </p>
<p>Most of us apply sunscreen because we are going to be in the sun. We put on a thin layer that is not too icky. Under these conditions, <a href="http://www.ncbi.nlm.nih.gov/pubmed/7726582">sunscreen actually doesn’t seem to make a lot of difference</a> to vitamin D production. </p>
<p>There’s a lot we don’t know about vitamin D. But we do know that Australia has the highest skin cancer incidence in the world: hundreds of thousands of skin cancers are removed each year at a cost of <a href="http://www.ncbi.nlm.nih.gov/pubmed/?term=sinclair+r+nmsc">more than $700 million</a> and there are over <a href="http://www.aihw.gov.au/acim-books/">2,000 deaths</a> from it. </p>
<p>Excessive sun exposure is the <a href="http://www.ncbi.nlm.nih.gov/pubmed/15753968">main cause of that problem</a>. Getting the balance between vitamin D levels and sun protection right is an important health goal. </p>
<p>More research is needed and it should be Australian research because our circumstances are different to those in the United States and Europe. We can’t just take results from there and use them here. </p>
<p>While a <a href="https://theconversation.com/theres-a-very-simple-solution-to-your-lack-of-vitamin-d-15409">simple solution</a> would be nice, an evidence-based one is preferable and worth pursuing. Stories about our epidemic of vitamin D deficiency drive excessive testing at high cost and unknown value. And they probably just end up selling more vitamin supplements. </p>
<p>But they also <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3705326/pdf/nutrients-05-00915.pdf">create confusion</a> and diminish people’s confidence and resolve to reduce excessive UV exposure. </p><img src="https://counter.theconversation.com/content/15814/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Robyn Lucas receives funding from National Health and Medical Research Council and Cancer Australia.</span></em></p><p class="fine-print"><em><span>Terry Slevin receives funding from Cancer Australia as an Associate Investigator on a study examining the impact of vitamin D supplementation and sun exposure and their impact on vitamin D levels. He is affiliated with Cancer Council Australia as Chair of the National Skin Cancer Committee. His employer, the Cancer Council Western Australia also sells sunscreen within its range of sun protection products.</span></em></p>Vitamin D has emerged as “the vitamin of the decade”, with a long and growing list of maladies supposedly caused through its absence or prevented through its bountiful supply. But is there adequate evidence…Robyn Lucas, Associate Professor of Epidemiology, Australian National UniversityTerry Slevin, Honorary Senior Lecturer in Public Health at Curtin University; Education & Research Director, Cancer Council WA; Chair, National Skin Cancer Committee, Cancer Council AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/120152013-02-05T19:01:22Z2013-02-05T19:01:22ZStudy finds slip, slop, slap message is slipping<figure><img src="https://images.theconversation.com/files/19979/original/fqqt6gvq-1360059479.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Australians are heeding the slip, slop, slap message, but skin cancer rates are still rising.</span> <span class="attribution"><span class="source">AAP/Tony Bartlett</span></span></figcaption></figure><p>Australians are becoming less attracted to having a suntan and fewer are being sunburned, but there’s been less improvement in wearing sunscreen in recent years, according to new research from the Cancer Council.</p>
<p>The research, published in the Australian and New Zealand Journal of Public Health, compared data from a national survey of more than 6,000 people, with data going back to 2003.</p>
<p>It found the proportion of adults desiring a tan fell from 39% in 2003/4 to 27% in 2010/11, and those getting sunburned at the weekend fell by 5% during the same period.</p>
<p>Despite this, one in five adolescents and one in eight adults still reported getting sunburned, and hat use has actually decreased over time among adolescents and adults.</p>
<p>Research author Terry Slevin, who is chair of Cancer Council Australia’s Skin Cancer Committee, wants more money to be spent on skin cancer prevention.</p>
<p>“The bottom line is we never see fast changes when it comes to public health.”</p>
<p>Despite positive changes to behaviour, the number of skin cancers reported is increasing, from 412,493 in 1997 to 767,347 in 2010, according to the Medical Journal of Australia.</p>
<p>The Cancer Council says the cost of treating these cancers exceeds $500 million per year.</p>
<p>“We are spending huge amounts treating cancers that are preventable,” Mr Slevin said.</p>
<p>“There’s a clear economic rationalist argument, if you take the long term view, that this is an investment Australia can make where we can have a clear cost saving.”</p>
<p>Rod Sinclair, professor of dermatology at Epworth Hospital said behavioural change is hard to achieve and hard to document.</p>
<p>“Until recently it was standard dogma that public education campaigns were a waste of money,” Professor Sinclair said.</p>
<p>“The Cancer Council Victoria first challenged that dogma and have now produced evidence that people will respond to public education campaigns and can be taught to modify pleasurable activities to protect their health.</p>
<p>The change is slow. The change is incomplete. The change is easily forgotten if the public education dollars stop flowing. However the potential benefits to both the Australian people and the Australian government in terms of reducing skin cancer justify continuing public education.”</p>
<p>Mr Slevin added that unlike anti-smoking campaigns and their simple “don’t smoke” message, skin cancer prevention required a more sophisticated approach to target specific behaviours, such as sunscreen use or hat wearing.</p>
<p>“With sun protection there are continuous variables so it’s a far more nuanced and subtle challenge that we face.”</p>
<p>For example, Mr Slevin said men were an area of focus that required further attention.</p>
<p>“When you look at the trend in terms of skin cancer rates and the gap between men and women there’s no doubt we need to focus on men.”</p>
<p>The data shows one in 14 men are diagnosed with melanoma before the age of 85, compared with one in 23 women.</p>
<p>Professor Sandra Jones, director of the Centre for Health Initiatives at the University of Wollongong said health communication campaigns were often subject to a range of competing behaviours and messages.</p>
<p>For example, she cited public debates about the “safety” of sunscreen, and the recent focus on Vitamin D deficiency as two examples of messages that deter people from sun protection.</p>
<p>But Professor Jones added that health communication campaigns needed reinforcement to remain top of mind. </p>
<p>“What we are seeing are small gains as a result of ongoing public communication campaigns. If these campaigns do not continue, we will almost certainly see these gains reverse.”</p>
<p>Professor Jones said health education campaigns do not work in isolation, and needed to be accompanied by other activities to address barriers to behaviour change. </p>
<p>She said such activities could include applying the “no hat no play” rule to secondary schools, ensuring school uniforms provide adequate sun protection, and monitoring changes in skin cancer incidence following the ban on tanning beds which comes into place in NSW next year.</p><img src="https://counter.theconversation.com/content/12015/count.gif" alt="The Conversation" width="1" height="1" />
Australians are becoming less attracted to having a suntan and fewer are being sunburned, but there’s been less improvement in wearing sunscreen in recent years, according to new research from the Cancer…Charis Palmer, Deputy Editor/Chief of StaffLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/118222013-02-04T03:32:23Z2013-02-04T03:32:23ZMonday’s medical myth: deodorants cause breast cancer<figure><img src="https://images.theconversation.com/files/19762/original/t2wynvdf-1359673803.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Based on the evidence, it's safe to dismiss this one as a myth.</span> <span class="attribution"><span class="source">Flickr/lism</span></span></figcaption></figure><p>The concern that using deodorants and antiperspirants might increase the risk of breast cancer has been around for <a href="http://www.salon.com/1999/05/25/anti_perspirant/">around for at least 15 years</a>, probably longer.</p>
<p>The theory suggests that either <a href="http://www.ncbi.nlm.nih.gov/pubmed/12210538">parabens</a>, a preservative previously used in some deodorants that acts as a weak form of oestrogen, or <a href="http://www.ncbi.nlm.nih.gov/pubmed/16045991">aluminium salts</a> used in many antiperspirants, enter the body and contribute to or cause breast cancer.</p>
<p>Studies detecting the presence of <a href="http://www.ncbi.nlm.nih.gov/pubmed/14745841">traces of paraben</a> and <a href="http://www.ncbi.nlm.nih.gov/pubmed/17629949">aluminium products in breast tissue</a> and breast tumour are put forward as evidence of the connection.</p>
<p>The other argument supporting this theory centred on the higher proportion of breast cancer lesions being located in the <a href="http://www.ncbi.nlm.nih.gov/pubmed/16080490">upper outer quadrant of the breast</a>. This is where deodorants and antiperspirants would come into most contact with breast tissue.</p>
<p>Others have observed there is simply more <a href="http://www.ncbi.nlm.nih.gov/pubmed/15767185">breast tissue</a> in that part of the breast. So if lesions are evenly spread, we would expect to find more disease in that part of the breast.</p>
<p>Another issue is measurement precision. As reported in the study that advanced the theory, between the years 1980 and 1996, there was a lack of compliance with recording cancer lesion location by breast quadrant. Only 17.5% of cases recorded cancer location by quadrant, making meaningful analysis difficult.</p>
<p>On the question of the presence of parabens in breast tissue or breast lesions, detectable measures in tissue does not in itself prove causation of disease. Breast cancers, like most solid tumours, develop their own access to the body’s blood as a means to grow. As a result, it’s likely that any substance that’s in the blood stream will be detectable in small amounts in the tumour tissue. But it doesn’t mean the detected substance caused the cancer.</p>
<p>Nonetheless, as a result of the stories circulating about the potential harms of parabens, most manufacturers of deodorants have ceased using these preservatives. Not because of a proven harm, but because of a suspicion (“market perception”) of possible harm, which ultimately affects sales.</p>
<h2>What does the evidence say?</h2>
<p>Studies aimed at determining if a connection between underarm products and breast cancer really exists have not been able to find a causal link. One <a href="http://www.ncbi.nlm.nih.gov/pubmed?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=12381712,24763424">study in 2002</a> looked at about 800 women with breast cancer and a similar number of matched controls. They asked about the use of antiperspirants and deodorants, and underarm shaving habits. They could not find any difference between those with and those without breast cancer for any of these behaviours.</p>
<figure class="align-left ">
<img alt="" src="https://images.theconversation.com/files/19769/original/nwxr5nwb-1359675181.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/19769/original/nwxr5nwb-1359675181.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=900&fit=crop&dpr=1 600w, https://images.theconversation.com/files/19769/original/nwxr5nwb-1359675181.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=900&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/19769/original/nwxr5nwb-1359675181.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=900&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/19769/original/nwxr5nwb-1359675181.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1130&fit=crop&dpr=1 754w, https://images.theconversation.com/files/19769/original/nwxr5nwb-1359675181.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1130&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/19769/original/nwxr5nwb-1359675181.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1130&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">The theory suggests parabens or aluminium salts used in antiperspirants enter the body and contribute to cancer.</span>
<span class="attribution"><span class="source">Image from shutterstock.com</span></span>
</figcaption>
</figure>
<p>Another small case control study, in <a href="http://applications.emro.who.int/emhj/1203_4/12_3-4_2006_478_482.pdf">2006 found</a> that 82% of the controls (women without breast cancer) and 52% of cases (women with breast cancer) used antiperspirants, indicating that using the under arm product might protect against breast cancer. While the study is too small to justifiably make such a claim, it certainly does not support the “antiperspirants cause cancer” story.</p>
<p>Reputable groups like the American <a href="http://www.cancer.gov/cancertopics/factsheet/Risk/AP-Deo">National Cancer Institute</a>, <a href="http://www.cancerresearchuk.org/cancer-info/healthyliving/cancercontroversies/deodorants/deodorants-and-cancer">Cancer Research UK</a>, the <a href="http://www.cancer.org/cancer/cancercauses/othercarcinogens/athome/antiperspirants-and-breast-cancer-risk">American Cancer Society</a> and most other major authorities suggest the link between deodorant or antiperspirant use and breast cancer is unconfirmed, or simply a myth.</p>
<h2>What about radiotherapy?</h2>
<p>Another contributing factor that perpetuates this myth is that patients undergoing radiotherapy are commonly advised to stop using antiperspirants during therapy, on the theory that the aluminium salts may influence the therapy. However a <a href="http://www.ncbi.nlm.nih.gov/pubmed/20002290">2009 Australian study</a> indicated that less than half of patients complied with this advice, with many forgetting (43%) or ignoring (10%) it.</p>
<p>Interestingly, this study also found, “Of the 233 women who routinely wore a deodorant but abstained during radiotherapy, 19% expressed a lot of concern about body odour and 45% were slightly concerned”. This suggests that many people see a clear benefit in using these products.</p>
<p>Even more recently, a <a href="http://www.ncbi.nlm.nih.gov/pubmed/22516385">Canadian study</a> found no evidence of antiperspirant use having any adverse effect on radiotherapy treatment for breast cancer.</p>
<p>It’s impossible to ignore that the majority of research on the possible link between underarm cosmetics and breast cancer comes from <a href="http://www.ncbi.nlm.nih.gov/pubmed?term=darbre%20p%20breast%20cancer">one research group</a>. And it seems despite the absence of evidence to support the link, their search to prove the theory is <a href="http://www.canceractive.com/cancer-active-page-link.aspx?n=2839&Title=Dr%20Philippa%20D%20Darbre%20patron%20of%20CANCERactive">unlikely to stop</a>.</p>
<p>Who knows, they may ultimately be proven correct. But based on the evidence from most of the other groups researching this question – it seems likely to remain nothing more than a myth.</p>
<p><em>For more cancer myths, visit Cancer Council’s <a href="http://iheard.com.au/">iheard website</a>.</em> </p>
<p><strong>Further reading:</strong></p>
<ul>
<li><p><a href="https://theconversation.com/mondays-medical-myth-natural-cancer-therapies-cant-harm-you-10315">Monday’s medical myth: natural cancer therapies can’t harm you</a></p></li>
<li><p><a href="https://theconversation.com/mondays-medical-myth-stress-causes-cancer-5313">Monday’s medical myth: stress causes cancer</a></p></li>
<li><p><a href="https://theconversation.com/mondays-medical-myth-the-pill-increases-your-risk-of-cancer-6931">Monday’s medical myth: the pill increases your risk of cancer</a></p></li>
<li><p><a href="https://theconversation.com/mondays-medical-myth-wearing-a-bra-to-bed-increases-your-risk-of-breast-cancer-8355">Monday’s medical myth: wearing a bra to bed increases your risk of breast cancer</a></p></li>
<li><p><a href="https://theconversation.com/mondays-medical-myth-were-not-getting-enough-sun-10205">Monday’s medical myth: we’re not getting enough sun</a></p></li>
</ul><img src="https://counter.theconversation.com/content/11822/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Terry Slevin does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>The concern that using deodorants and antiperspirants might increase the risk of breast cancer has been around for around for at least 15 years, probably longer. The theory suggests that either parabens…Terry Slevin, Honorary Senior Lecturer in Public Health at Curtin University; Education & Research Director, Cancer Council WA; Chair, National Skin Cancer Committee, Cancer Council AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/116332013-01-23T03:30:24Z2013-01-23T03:30:24ZSunscreen, skin cancer and the Australian summer<figure><img src="https://images.theconversation.com/files/19241/original/9b7thvft-1358292872.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Sunscreen shouldn't be your only defence against the sun – clothing, hats, sunglasses and shade are equally important.</span> <span class="attribution"><span class="source">Flickr/stray kat</span></span></figcaption></figure><p>With the long, hot Australian summer comes the imperative to manage the country’s enormous skin cancer risk.</p>
<p>Along with the growing raw numbers (11,545 skin cancer cases diagnosed in 2009) and <a href="http://www.aihw.gov.au/acim-books/">rates of melanoma</a>, the numbers of non-melanoma skin cancers (NMSC) are going off the charts. Men are disproportionately affected, with one in 14 blokes diagnosed with melanoma before the age of 85, compared with one in 23 women. </p>
<p>Two months ago the <a href="http://www.ncbi.nlm.nih.gov/pubmed/23163687">Medical Journal of Australia reported</a> the total number of NMSC treatments increased from 412,493 in 1997 to 767,347 in 2010, and the authors estimated the number of treatments would increase to 938,991 by 2015. </p>
<p>The costs estimate – which I understand doesn’t include the patient’s out-of-pocket expenses – was over half a billion dollars in 2010. This is an enormous health burden unique to Australia and our friends across the Tasman.</p>
<p>Slip, slop, slap was born to help Australians adapt to the unique environment in which we live. More recently we’ve added seek (shade) and slide (on sunglasses) to slipping (on the shirt) and slapping (on the hat). But it’s the slopping on of sunscreen that has caused the most controversy in the almost 20 summers during which I’ve been banging on about skin cancer.</p>
<p>Almost every summer I’ve been brought in to the newest debate about the dangers, the changes, the failings or the confusions about sunscreen. And this summer is no different.</p>
<p>This summer attention has focused on the introduction of the <a href="http://theconversation.com/mondays-medical-myth-spf50-sunscreen-almost-doubles-the-protection-of-spf30-3949">new standard of SPF50+</a>. When it comes to SPF50+ the story is a reasonably simple one. A little better than SPF30+ is good – but we still need to put enough of the stuff on to achieve the claim on the bottle. </p>
<p>Sunscreen is usually <a href="http://www.ncbi.nlm.nih.gov/pubmed/8876111">applied in half or less of the dose necessary</a> to achieve the sun protection claimed on the bottle.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/19327/original/6wfmjftb-1358393255.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/19327/original/6wfmjftb-1358393255.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/19327/original/6wfmjftb-1358393255.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/19327/original/6wfmjftb-1358393255.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/19327/original/6wfmjftb-1358393255.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/19327/original/6wfmjftb-1358393255.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/19327/original/6wfmjftb-1358393255.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=503&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">A number of debates about sunscreen have raged over the past 20 years.</span>
<span class="attribution"><span class="source">Michael Newman</span></span>
</figcaption>
</figure>
<h2>What does the SPF number mean?</h2>
<p>SPF stands for Sun Protection Factor and the number reflects how protective a sunscreen is against UVB radiation, which causes sunburn and increases <a href="http://www.cancer.org.au/about-cancer/types-of-cancer/skin-cancer.html">skin cancer</a> risk. </p>
<p>SPF15, for example, filters about 94% of UVB radiation, leaving about 1/15th of the radiation getting through. But it also means skin that would normally burn in 10 minutes in the midday summer sun would take about 150 minutes or 15 times as long before the burn would occur. So the lotion “screens” but does not “block” the sun.</p>
<p>For SPF30+ it’s the same story: about 1/30th gets through so 96.7% of the UVB rays are filtered out. And with SPF50+ – you guessed it – 1/50th gets through, or about 98% is filtered out.</p>
<p>So while there might sound like a world of difference between the numbers 30 and 50, we’re talking just 1.3% improvement in UVB protection.</p>
<p>The <a href="https://theconversation.com/mondays-medical-myth-spf50-sunscreen-almost-doubles-the-protection-of-spf30-3949">new standard</a> applying to sunscreens claiming an SPF in excess of 30+ will require a better standard of UVA protection and this is probably the most important advance in this recent change. Also, misleading claims of sunscreen being “waterproof”, “sweat proof” or the term “sunblock” are no longer allowed.</p>
<h2>Sun protection</h2>
<p>It’s important to understand that sunscreen is a useful adjunct to other sun protection measures. Rather than being our first line of defence, it should be the last. Not only do we seldom use enough, but it’s easily sweated off and rubbed off as we towel down or rub water from our eyes.</p>
<p>But why should we bother to mess about with the funny white creams anyway? Can’t we just wear protective clothing, hats and use shade, or better still stay indoors? </p>
<p>Well, of course we can and should use all these strategies. But sunscreen is a sun protection strategy proven by randomised controlled trial to prevent skin cancer.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/19328/original/nkqr66vh-1358393658.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/19328/original/nkqr66vh-1358393658.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=338&fit=crop&dpr=1 600w, https://images.theconversation.com/files/19328/original/nkqr66vh-1358393658.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=338&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/19328/original/nkqr66vh-1358393658.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=338&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/19328/original/nkqr66vh-1358393658.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=424&fit=crop&dpr=1 754w, https://images.theconversation.com/files/19328/original/nkqr66vh-1358393658.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=424&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/19328/original/nkqr66vh-1358393658.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=424&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
<figcaption>
<span class="caption">Sunscreen manufacturers are no longer allowed to claim their products are waterproof.</span>
<span class="attribution"><span class="source">Flickr/bookgrl</span></span>
</figcaption>
</figure>
<p>The Nambour study conducted in South East Queensland in the early 1990s found the use of sunscreen (then the old SPF15+) reduced the <a href="http://www.ncbi.nlm.nih.gov/pubmed/10475183">risk of squamous cell carcinomas</a> (the second most common non-melanoma skin cancer) by 12% and <a href="http://www.ncbi.nlm.nih.gov/pubmed/21135266">melanoma by about half</a>.</p>
<p>So, as we get closer to seeing SPF50+ sunscreen land on the shelves of our local shops remember the famous all-encompassing 1998 life advice speech of disputed origins <a href="http://www.planetgary.com/sunscreen.htm">“Wear sunscreen”</a> – and heed the advice. It’s still a good tip.</p>
<p>Here are a few other simple sunscreen tips:</p>
<ol>
<li><p>Sunscreen shouldn’t be used as the first and last defence against the sun. Don’t forget the other “S"s – Slip on a Shirt, Slap on a Hat, Seek some shade and Slide on your sunnies. </p></li>
<li><p>Don’t throw out the old SPF30+ sunscreen. Cancer Council Australia recommends using any water resistant, broad-spectrum sunscreen with an SPF of at least 30, so use up what you have.</p></li>
<li><p>Whether it’s current SPF30+ or the new SPF50+ sunscreen, put plenty on. About a teaspoon for each limb and a teaspoon for the front of the body and one for the back.</p></li>
<li><p>Reapply every two hours. Regardless of the SPF, all sunscreens can be washed off, towelled off or wiped away when we rub that last wave out of our eyes.</p></li>
<li><p>Learn to read the <a href="http://www.cancer.org.au/preventing-cancer/sun-protection/uv-alert/">UV index</a>. Under UV three you can get some safe sun time and a little vitamin D.</p></li>
</ol><img src="https://counter.theconversation.com/content/11633/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Terry Slevin works for Cancer Council WA. The Cancer Council sells a range of sunscreens, the royalties of which fund cancer research, prevention and support programs </span></em></p>With the long, hot Australian summer comes the imperative to manage the country’s enormous skin cancer risk. Along with the growing raw numbers (11,545 skin cancer cases diagnosed in 2009) and rates of…Terry Slevin, Adjunct Professor, School of Psychology and Speech Pathology, Curtin University; Education and Research Director, Cancer Council WA; Chair, Occupational and Environmental Cancer Committee, Cancer Council AustraliaLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/116702013-01-17T03:32:10Z2013-01-17T03:32:10ZCall for policymakers to consider genetic link to soft drink consumption<figure><img src="https://images.theconversation.com/files/19324/original/xcr7zzqc-1358392482.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">If policymakers understood what drives people to drink sugary drinks, they make take a different approach.</span> <span class="attribution"><span class="source">Ava Rose</span></span></figcaption></figure><p>Policymakers should understand the urge to drink soft drinks is genetically determined, rather than being solely a lifestyle choice, argue endocrinologists from the Garvin Institute of Medical Research.</p>
<p>A study published in the New England Journal of Medicine last year showed a direct correlation between consumption of sugary soft drinks, obesity and genetic predisposition to weight gain.</p>
<p>Now, Associate Professor Jerry Greenfield has joined other researchers from the Garvan Institute in calling for more attention to be given to the genetic factors behind obesity.</p>
<p>They argue if policymakers better understand the drive to eat is not a factor that people can easily overcome, it might help inform public health policy. </p>
<p>“Policy should reflect the scientific basis of food intake – in other words, people who eat too much and put on weight are not just over consuming because they are greedy, they actually have a very strong drive to eat,” Professor Greenfield said.</p>
<p>The call comes as three major Australian health organisations have stepped up efforts to tackle the consumption of sugary drinks with the launch of a television campaign.</p>
<p>“Sugary drinks shouldn’t be part of a daily diet… yet they’re being consumed at levels that can lead to serious health issues for the population,” said Craig Sinclair, chair of the Public Health Committee at Cancer Council Australia.</p>
<p>The Cancer Council, together with Diabetes Australia and the National Heart Foundation, are calling on the Federal Government to implement restrictions on the marketing of sugary drinks to children, and also want Treasury to investigate a tax on sugary drinks.</p>
<p>A 2007 survey found almost half of children aged 2 to 16 consumed sugary drinks daily.</p>
<p>There is some evidence, however, that a growing number of Australians are cutting back on sugar consumption.</p>
<p>A survey of 1,511 Australians conducted late last year by Goulburn Valley found 72% were aware of the “sugar is bad for you” debate, and half those surveyed with young families (mainly preschool aged children) agreed you should limit your fruit consumption to cut down on sugar intake.</p>
<p>The official Australian Guide to Healthy Eating recommends adults consume between two and five serves of fruit a day, depending on age and gender.</p><img src="https://counter.theconversation.com/content/11670/count.gif" alt="The Conversation" width="1" height="1" />
Policymakers should understand the urge to drink soft drinks is genetically determined, rather than being solely a lifestyle choice, argue endocrinologists from the Garvin Institute of Medical Research…Charis Palmer, Deputy Editor/Chief of StaffLicensed as Creative Commons – attribution, no derivatives.