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Monday’s medical myth: fish oil is good for heart health

Did you hold your nose and take your daily dose of fish oil this morning? Or perhaps you opted for an odour-free capsule? Well, you’re not alone. Around one in four Australians take fish oil supplements…

One in four Australians take fish oil but the latest evidence shows it won’t improve the health of your heart. Flickr/wine me up

Did you hold your nose and take your daily dose of fish oil this morning? Or perhaps you opted for an odour-free capsule? Well, you’re not alone. Around one in four Australians take fish oil supplements to improve their health. After all, it’s supposed to be good for the heart. Right?

The Heart Foundation even has a Fish Oil Program aimed at increasing awareness of the benefits of marine-derived omega 3 fatty acids on heart health. Its 2008 Position Statement on Fish Oil recommended adults consume at least 500mg of omega-3 a day to lower the risk of heart disease.

If you’re interested in learning more about the complexities of fatty acid metabolism, you can find readable technical summaries in the opening part of this paper or a more comprehensive version on Wikipedia. But in short, researchers are interested in the potential benefits of docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA) and docosapentaenoic acid (DPA).

The fish oil story reflects the challenges involved in translating research evidence into community knowledge and behaviour. And it shows why those who stand by evidence in medicine must be prepared to give up their most cherished beliefs if the science demands it.

The Heart Foundation 2008 Position Statement is a good place to start. It is a serious public health document which takes a balanced, evidence-based approach.

A table in the document sets out the levels of evidence supporting the rationale for its recommendations. But only one finding has level one (the highest level) evidence to support it – that is, the statement that fish oil supplements have a favourable effect on serum triglyceride levels and HDL (good) cholesterol levels.

Although one might assume this to be a good thing, there is not a similar level of support for the direct link between fish oil and improved heart health. It may be that this positive effect on blood lipid ratios is too small to have a useful benefit when applied routinely to real, paying customers outside of clinical trials.

Most of the other planks of the position have level two or three evidence, which translates to positive results in individual studies without support from meta-analysis or systematic reviews of multiple studies. The number of studies with negative or inconclusive results does not affect these ratings.

The Heart Foundation noted this shortfall and designated areas for further study which include doing higher-level reviews and better studies with robust methodology. As an organisation which strives to use the best evidence to form policy, I expect it will update and amend its recommendations to reflect the findings of such new studies as they come in.

Omega 3 supplements aren’t effective at preventing heart attacks. jcoterhals

The biggest gap in the research on fish oil supplements has been between their effects in test tubes and small pilot studies, and the real world of clinical practice. A definite mechanism for how omega 3 fatty acids provide cardiac protection has never been agreed on, which makes predicting clinical effects in real patients difficult.

An early systematic review in 2006 supported fish oil for heart health. But reading the body of the paper, it’s hard to see how the researchers came to such a positive conclusion. They comment throughout on the variable methods of studies reviewed and the mixed outcomes reported. They mostly favour a small positive effect but don’t consistently point the same way.

There are also other, similar reviews from the early 2000s which draw mixed conclusions.

In the last few months there have been major systematic reviews in the Archives of Internal Medicine, the Annals of Internal Medicine and the Journal of the American Medical Association (JAMA) which have all separately failed to support a clear effect on people in the real world.

The JAMA study demonstrates pretty comprehensively that omega 3 supplements aren’t effective at preventing cardiac problems such as heart attacks, stroke, sudden death and arrhythmias. What makes this study more credible is that it has included both dietary and supplement studies. Whether you are getting your omega 3s from a capsule or from tins of tuna, it seems unlikely that they are doing much good.

So what does this all mean for those taking omega 3 supplements?

Well, fish oil may be reasonable as an add-on therapy for very high-risk cardiac patients who can’t tolerate other, more effective treatments.

Research on fatty acid supplementation is likely to continue and some specific use may still be found for such supplements. The evidence that omega 3 can reduce the symptoms of inflammatory arthritis, for example, still appears promising.

Efforts to encourage Australians to eat more fish should push on, because preferring fish to red meat is still a worthwhile change for other health reasons.

But it’s becoming increasingly clear that having a quarter of the population on fish oil as a preventive supplement is an unjustifiable expense. I will await the self-regulatory response from advertisers of fish oil products to this avalanche of new evidence with interest, as should the Therapeutic Goods Administration.

Join the conversation

71 Comments sorted by

Comments on this article are now closed.

  1. Charles Alpren

    logged in via Twitter

    Thank you for this article. I was, as you predict, a bit annoyed to realise that I needn't have been taking the fish oil, and relieved because most of the time I forgot it anyway. However, I'm interested in your opinions on its use for primary prevention of heart disease. As far as I can tell, all the meta-analyses were on secondary prevention, and my experience is that most people take it for primary prevention (ie they have no previous heart disease or risk factors for heart disease) and often get an imporvement in their lipid profile as a result. Obviously, this is for only a small reduction in risk, but it is people who have reasonable diets, whose lipid profile isn't bad enough to need prescription medication, but could be a bit better that go for fish oil. What are your thoughts for them?

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    1. Michael Vagg

      Clinical Senior Lecturer at Deakin University School of Medicine & Pain Specialist at Barwon Health

      In reply to Charles Alpren

      Thanks Charles for this comment. I was going to try to explain primary and secondary prevention but it was making the article a bit long. It's very important though to acknowledge that the met-analyses quoted are indeed almost entirely about secondary prevention, ie reducing risk in those with established risk factors and asymptomatic disease.

      Large trial data about dietary DHA/EPA are lacking but some are underway such as this one
      http://www.ncbi.nlm.nih.gov/pubmed/21986389

      There's no doubt that marine omega 3 supplements can improve lipid profiles and reduce thrombotic tendency but the real question is whether the effect size is clinically relevant to recommend primary prevention. The current position would be that there is no really good data on primary prevention of cardiac disease, but if there is a lack of effect in secondary prevention you would not expect to see much benefit in a healthy primary prevention population.

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  2. Mat Hardy

    Lecturer in Middle East Studies at Deakin University

    So on to the next two mega claims for fishy / krilly oils:

    1) Will it help my arthritis?
    2) Assuming my kids are relatively normal behaviorally and eat a balanced diet, do fish oil capsules make them any better at school?

    I would appreciate knowing the answer here. At least for question 2, wading through the literature seems to indicate no great benefit as far as I can see. But then, I am a Humanities lecturer.

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    1. Michael Vagg

      Clinical Senior Lecturer at Deakin University School of Medicine & Pain Specialist at Barwon Health

      In reply to Mat Hardy

      Thanks Matt

      Fish oil can help the symptoms of inflammatory arthritis, such as rheumatoid or lupus arthritis. It is of no benefit in osteoarthritis ('wear and tear type'). It can be helpful for short-term relief of inflammatory tendon or ligament injuries but high doses are needed. There is no evidence that omega 3 supplements can affect the long-term prognosis of such conditions, so it's like paracetamol or hot packs in that respect.

      Despite much hype (such as this review http://www.ncbi.nlm.nih.gov/pubmed/22841917

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    2. Dianna Arthur

      Environmentalist

      In reply to Michael Vagg

      Thanks for this interesting article.

      I do take fish capsules - one in the morning and one at night. Not because of any heart problems, my heart is fine despite having rheumatic fever when a child. However, due to fibro myalgia (and maybe just getting older) I find that the fish oil helps. My joints are more painful in the morning if I miss the nightly capsule.

      I would like to ask you about krill oil - I am concerned that this latest "cure-all" is further depleting the basis of the marine food chain. Do you know how either krill or fish oil is sourced?

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    3. Michael Vagg

      Clinical Senior Lecturer at Deakin University School of Medicine & Pain Specialist at Barwon Health

      In reply to Dianna Arthur

      That's a very good question Dianna.

      There are various sources for fish oil ranging from aquaculture to deep sea fishing. It seems to vary a lot by manufacturer. Krill oil appears to be mostly sustainably (more or less) sourced from only one or two large suppliers who have strict environmental controls. These safeguards are held responsible for the significantly higher cost of krill oil. There is no doubt that krill is an absolutely fundamental part of the food chain, and there is a lot of work being done on the problem of sustainability of marine sources of these products.

      My suggestion is to contact the manufacturer of the product you use and see where they are sourcing it from. If you don't like their response...switch to one which is environmentally responsible.

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    4. Dianna Arthur

      Environmentalist

      In reply to Michael Vagg

      Thanks for your reply.

      I will do a little research into the brand I of fish oil I use. I raised the question more as an issue; that we need to consider the source and sustainability of whatever we consume - be it cleaning products, furniture, electronics through to food. I am think I fail more often than succeed with responsible purchases - this is more due to availability and cost. Easier to be green when one is sufficiently cashed up. Although there are some really inexpensive things such as…

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    5. Robert Peers

      General Practitioner

      In reply to Mat Hardy

      Hi Mat, I think Michael Vagg might be right: most kids have about the right amount of fish oil in their brain membranes, mainly due to the brain being very jealous of its precious dietary nutrients, which are hard to deplete. That goes for fish oil and zinc, to name two. However, we do have a problem with fish oil, when the child eats refined omega-6 seed oils: these common vegetable oils lose 30% of their vitamin E during steam-refining. They are already linked to Alzheimer's disease, and my own…

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    6. Emma Anderson

      Artist and Science Junkie

      In reply to Michael Vagg

      So are you also saying that people with inflammatory or inflammation related disorders *might* benefit from fish oil supplements as per when it relates directly to the inflammation, but, if that inflammation related disorder has negative consequences for the nervous system (let's say it has a primary or further relationship with neural degeneration or demyleination) the fish oil won't be of any help in repairing it?

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    7. Michael Vagg

      Clinical Senior Lecturer at Deakin University School of Medicine & Pain Specialist at Barwon Health

      In reply to Emma Anderson

      Thanks Emma
      I think you've summarized that about right.

      There is a huge gap between the observed effects of omega 3's on lab rats and cell cultures and the logical clinical benefits of those effects in real life. Nobody argues that they can reduce the production pro-inflammatory signal molecules, but whether these effects are enough to alter the course of disease processes is still open for debate. The current evidence from clinical trials suggests that there is no useful benefit in preventing degeneration of CNS tissue in conditions like dementia, stroke and MS.

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    8. Emma Anderson

      Artist and Science Junkie

      In reply to Michael Vagg

      Thanks for the reply though.......I am not seeing how this answers my question about repairing existing damage. I was wondering if people who already have demyleination can perhaps give their ogliodendrocytes some tools for the job by eating Omega-3s or anything else for that matter?

      Not the same as preventing. Although in MS, what I've read *so far* in executive summary type of thing is 1) dunno what causes it 2)something to do with inflammatory interleukins and a dodgy BBB and a bunch of other…

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    9. Buzzy Kerbox

      logged in via email @gmail.com

      In reply to Emma Anderson

      Emma if you are interested in MS specifically have a look at Terry Wahls approach, she has a well known TED talk on youtube giving a basic run down on what helped her but I believe what also gives some insight into several different diseases and how they likely develop, due to gradual mitochondria degradation and shrinking brains; simply that we are living off inadequate food sources. Her talk lays out disease prevention better than anything I have ever seen, it also shows prevention is a full time…

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    10. Emma Anderson

      Artist and Science Junkie

      In reply to Buzzy Kerbox

      Not off topic for me! Will look it up.

      Does ME/CFS have demyleination as a symptom though? Never been clear on that or it's relationship with fibromyalgia, if any.

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    11. Buzzy Kerbox

      logged in via email @gmail.com

      In reply to Emma Anderson

      Emma ME is basically inflammation of the brain and or spine so there is no doubt the myelin shealth has been compromised, the cognitive symptoms in CFS/ME are generally the most devastating and debilitating which is what most people do not understand about the condition. But it can vary somewhat from person to person and I am not sure how prevalent it is in Fibro, I think this has more of an emphasis on pain/join issues.

      I take it that issues with the myelin sheath in MS is what is present on…

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    12. Emma Anderson

      Artist and Science Junkie

      In reply to Buzzy Kerbox

      Thanks for the email and offer. I'll contact you.

      RE: ME/CFS That sounds awful. What kind of inflammation?

      Re: Wahls. It's an interesting idea, although what I've learned is that what is good for some ain't good for others. My body can't stand dairy, for example. Other people thrive on it. So when someone says they reversed a disease without a known cause using diet, I raise my eyebrows like this author here seems to have: http://intelligentguidetoms.wordpress.com/2012/04/09/some-versions-of-the-paleo-diet-may-make-your-multiple-sclerosis-worse

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  3. Geoff Russell

    Computer Programmer, Author

    I'd summarise the evidence as "The beneficial effects of fish oil vanish as the quality of the research approaches that of a double blind placebo trial, in which case it does nothing at all" ... based on the studies you
    cite and the Cochrane Collaboration meta-analysis DOI:10.1002/14651858.CD003177

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  4. Edward John Fearn

    Hypnotherapist and Naturopath

    Thanks Michael,

    I tried to point out the favourable effects on serum triglyceride levels and HDL (good) cholesterol levels on your previous article, but it was closed for comment early. I was also going to bring up the recommendations of the heart foundation and other bodies, and was going to put forward that waiting for these organisations to evaluate this study and put forward changes to their recommendations accordingly would be a prudent course of action.

    However since you have covered all of these issues and more in your current piece, it seems that I have nothing more really to add.

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  5. Lynne Newington

    Researcher

    So many long living Australians were reared on Saunders Cod Liver Oil and Malt, especially those .who had suffered rheumatic fever.
    I would still recommend it, these days they don't come combined.

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    1. Geoff Russell

      Computer Programmer, Author

      In reply to Lynne Newington

      I had a Swiss friend who used to swear that elderly swiss farmers owed
      their longevity to cheese fondues. He had his first stroke at 49.

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    2. Sue Ieraci

      Public hospital clinician

      In reply to Lynne Newington

      Ms Newington - cod liver oil is a source of vitamin D, but can do little if anything following rheumatic fever, which causes structural changes to the heart and its valves due to infection (quite different from the plaque in coronary arteries that causes ischaemic heart disease).

      On what information do you base your recommendation?

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    3. Geoff Russell

      Computer Programmer, Author

      In reply to Lynne Newington

      Yes, of course, the similarity was in the lack of quality in the evidence for the belief. Every elderly person has a theory on how they came to be old and more than a few younger people regard such theories as evidence. As Sue asks: if you have evidence, please supply it.

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    4. Lynne Newington

      Researcher

      In reply to Sue Ieraci

      Cod liver oil and malt, check the benefits.
      Your grandparents or an old GP would be a good scource of information, life experience you know, it does count for something, even in these scientific days.
      Unfortunately mothers have to be shown how to do everything, where as example commonsense and intutition have gone by the wayside.

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    5. Lynne Newington

      Researcher

      In reply to Geoff Russell

      Sue's reply is for you as well Geoff.
      Amazing how things are coming back into vogue, but with different packaging and price tag.

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    6. Sue Ieraci

      Public hospital clinician

      In reply to Lynne Newington

      My Newington - my grandparents ate very healthy diets, but used neither cod liver oil nor malt - they just ate good foods. For healthy oils they ate fish and olives, for Vitamin B they ate grains, eggs, fruit and vegetables.

      As a self-declared "researcher", you put your health recommendations down to "commonsense and intuition"? How would we know about nutrients and vitamins if it weren't for science?

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    7. Sue Ieraci

      Public hospital clinician

      In reply to Lynne Newington

      Geoff - the reply was essentially "because I say so".

      There is no need for the vogue supplements - whatever the packaging or price tags. All those nutrients can be found in good foods - all easily available to those of us who don't live in remote communities.

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    8. Lynne Newington

      Researcher

      In reply to Sue Ieraci

      The benefits are well known, and science has often confirmed this. I suppose you feel the same way about vitamin C.
      Research.

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  6. Sean Lamb

    Science Denier

    I think calling it a medical myth is overstating the negative evidence somewhat.
    For example the JAMA study reported over 7000 deaths out of 68000 patients, this suggests that there might be little added benefit when already being treated with state of the art medication (the only ethical way to run such a trial). But is that really so surprising? These medications may be interfering in the pathways where dietary supplements might be expected to function.
    But that is not the reason most people…

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    1. Michael Vagg

      Clinical Senior Lecturer at Deakin University School of Medicine & Pain Specialist at Barwon Health

      In reply to Sean Lamb

      Sean, science is not about trading support for beliefs. It's not politics after all.

      I'm not sure why you think there is denial of the likely link between oral health and heart disease. There is a plausible mechanism and some supportive evidence of reasonable quality, but it's hard to tease out whether it is a causative association, given the considerable overlap between risk groups for poor dental health and poor cardiac health. See here for a summary http://www.ncbi.nlm.nih.gov/pubmed/22514251

      I agree that small effects of fish oil may be hard to see in patients already treated with effective risk factor management. This tends to be more consistent with the null hypothesis than with the notion that fish oil has a definite treatment effect.

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    2. Sean Lamb

      Science Denier

      In reply to Michael Vagg

      Yes, well a lot of cardiologists don't like the idea - the fact that flossing teeth might be the magic bullet offends their self-esteem.

      It might be worth getting acquainted with why omega-3 fa are seen as essential fatty acids
      http://en.wikipedia.org/wiki/Essential_fatty_acid_interactions
      where they both interfer with Arachidonic acid both by competitive inhibition but also with their own signalling compounds. The field is still poorly characterised and I expect many of the researchers are making too dramatic claims. Nonetheless, I am sure these interactions are an essential part of our biology. Like vitamins, a deficiency will surely lead to problems, but how low of intake you might need before you could be considered deficient and how you would assess such a deficiency are different levels.

      At any rate I think it is wrong to call it a myth on the basis of the material you present.

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    3. Sue Ieraci

      Public hospital clinician

      In reply to Sean Lamb

      Sean Lamb - perhaps you haven't met "a lot of cardiologists", because the link between dental health and heart health is well-established. It's not about lipids, though - it's about infection and endocarditis.

      You say "Nonetheless, I am sure these interactions are an essential part of our biology."

      On what basis are you "sure"?

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    4. Sean Lamb

      Science Denier

      In reply to Sue Ieraci

      Dr Ieraci, you are right of course, a cardiologist would never deign to speak to me. I was basing my assessment on the statements of the American Heart Association
      http://www.reuters.com/article/2012/04/18/us-usa-health-gums-idUSBRE83H1AC20120418

      The reason I am sure is I believe in intelligent design and I am sure Paley's watchmaker would not have engineered so much complexity in the lipidome without in playing a significant purpose.

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    5. Venise Alstergren
      Venise Alstergren is a Friend of The Conversation.

      photographer, blogger.

      In reply to Sean Lamb

      As a person who has endured much dental medication-I'm learning to transcend it-I've been informed of the link between infection and dental problems. However, this is the first time I've read of a link between dental problems and heart attacks. I hope everyone is wrong here, as, thus far, my heart has been fantastic.

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    6. Sue Ieraci

      Public hospital clinician

      In reply to Venise Alstergren

      Venise, the relevant extract from Sean's link says this:
      "Because there have been hundreds of studies on the subject, Lockhart said, "If there were a strong causal link between atherosclerosis and periodontal disease, or if atherosclerosis could be cleared up by treating periodontal disease, we'd know it by now."

      It has been long known that poor dental and gum health, with the potential for entry of organisms into the blood stream, can cause endocarditis, which damages heart valves. People with artifical valves are particularly at risk.

      "Heart attack" is quite different - generally meant to refer to the blockage of a coronary artery causing damage to heart muscle from lack of blood. I have not seen evidence of a direct link between coronary artery occlusion and dental health.

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  7. Buzzy Kerbox

    logged in via email @gmail.com

    It is hard to take any study seriously looking at the effect of fish oil as a treatment for people who have already developed heart disease but as you state early in the article subjects like this can show the challenge of collecting data, allowing for other variables in diet and lifestyle then coming to any conclusions.

    Really what is needed is a large scale study over an extensive period of time, probably decades which also to some extent allows for variables in diet, because I am afraid many…

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  8. Laurie Willberg

    Journalist

    The benefits of omega 3 fish oil supplements are well-established for the prevention of inflammation -- which is one of it's main benefits in preventing heart disease in the first place.
    http://www.sciencedaily.com/releases/2012/05/120515151036.htm
    There have been studies of Alaskan Eskimos that show a virtually non-existent risk of high blood pressure and cardiovascular disease when indigenous peoples consume their traditional diet which is exceptionally high in omega 3 fish oils. When the same…

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    1. Geoff Russell

      Computer Programmer, Author

      In reply to Laurie Willberg

      The eskimo "studies" began as a comment in a 1975 paper, got cited in a 1991 paper in the Lancet and has been going the rounds ever since thanks to people who don't bother chancing claims they like back to their source. It wasn't until 2003 that somebody actually decided to examine data and found: "Mortality from stroke is similar or probably higher among the Inuit than among other western populations. The evidence for a low mortality from Ischemic Heart Disease is fragile and rests on unreliable mortality statistics."

      http://www.ncbi.nlm.nih.gov/pubmed/12535749

      As for Wikipedia ... the quality varies among subjects, but I'd say its generally more reliable than any of our daily newspapers in Australia ... at least it gets fact checked, and most claims are referenced!

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    2. Michael Vagg

      Clinical Senior Lecturer at Deakin University School of Medicine & Pain Specialist at Barwon Health

      In reply to Laurie Willberg

      Laurie

      I'll see your 2009 meta-analysis and raise you 3 2012 meta-analyses! The weight of evidence is now that even though there are measurable changes in lipid profile and inflammatory markers, this does not seem to be enough to have a clear practical benefit.

      Perhaps you didn't check the Wikipedia link, but when I was putting this article together, it looked to me like a comprehensive, accessible and easy-to-read summary for the general reader about the whole complex area of lipid metabolism. As Geoff has pointed out, many of the medical articles on Wikipedia are quite good as summaries that allow the average interested reader to get some basic facts about a specialist topic.

      I think it's perhaps an unintended irony on your part that you can have a go at me for linking to a well-researched Wikipedia article, right after having linked to a press release to support your own sweeping generalizations!

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    3. Laurie Willberg

      Journalist

      In reply to Michael Vagg

      Not enough to irrefutably undo the 2009 study or convince anyone to ditch omega 3 fish oil supplementation. It's far more important for people to realize that cheap fish oil supplements are likely contaminated with toxins like mercury so should shop carefully, and that variations in EPA and DHA content can have different effects.
      Science Daily doesn't tend to publish information that isn't fact-checked, and Wikipedia has indeed been corrupted.
      Most people who use orthomolecular medicine are not interested in "basic summaries" and don't rely on Wikipedia.

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    4. Michael Vagg

      Clinical Senior Lecturer at Deakin University School of Medicine & Pain Specialist at Barwon Health

      In reply to Laurie Willberg

      The target audience for this article is not just orthomolecular enthusiasts though!

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    5. Buzzy Kerbox

      logged in via email @gmail.com

      In reply to Laurie Willberg

      Laurie another serious aspect about the quality of fish oil people are not recognising is that Omega 3's are very light and oxygen sensitive, how they are processed, packaged and stored are all important aspects to the quality of the product before it goes into your mouth.

      Buying cheap fish oils, especially capsules is like Russian roulette, you can not be sure of the quality control of toxins from the fish as you say but also the exposure to oxygen and light during the processing; spoilt fish oil can be dastardly for your health and unless you are breaking open your capsules at room temperature to check the health of the oil inside you will have no idea; refrigeration will mask this as well which is why it needs to be done at normal temp.

      There is also a reason quality brands come in a blue glass bottle, it is to protect the oil from exposure to light.

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    6. Peter Reefman

      Project Manager

      In reply to Buzzy Kerbox

      The toxins can be a significant aspect, especially if the fish oil comes from larger marine species with toxin accumulation up the food chain.

      And while I've stopped giving my wife fish oil capsules for a while, I AM now a bit disturbed that they came in white plastic containers with little in the way of shielding from exposure to light!

      Sue's position of a balanced diet seems to synch more and more with the weight of in-depth sceintific analysis. I'll stick with that and minimise my contributions to the supplements/CAMS economy.

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    7. Laurie Willberg

      Journalist

      In reply to Michael Vagg

      Orthomolecular medicine is the practise of nutritional medicine. Researchers and specialists in that field are far more likely to have a higher background knowledge of not only published studies but of those that have not been referenced in major venues as well. The Journal of Orthomolecular Medicine is free to all but not referenced on MedLine which deprives the public of the knowledge of a valuable tool.
      A dependance on published studies in major journals becomes rather fatuous when some conclude…

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  9. Steve Brown

    logged in via email @yahoo.com.au

    "Well, fish oil may be reasonable as an add-on therapy for very high-risk cardiac patients who can’t tolerate other, more effective treatments."

    In the DART-2 trial, men with stable angina who were taking fish oil capsules experienced a higher risk of cardiac death.

    http://www.ncbi.nlm.nih.gov/pubmed/12571649

    Fish oils are dangerous. They're immunosupressive, hepatotoxic and neurotoxic, among other things:

    http://www.functionalps.com/blog/2011/11/26/fish-oil-toxicity/

    Funny how the supplement manufacturers didn't tell us about THAT research.

    Don't expect the Heart Foundation to amend their recommendations in line with the evidence. These dinosaurs are still waging a very silly 1950's era campaign against saturated fat while preaching the benefits of seed oils which are now recognized to be toxic in just about every way imaginable.

    They should have been sued into oblivion years ago.

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    1. Laurie Willberg

      Journalist

      In reply to Steve Brown

      "experienced a higher risk of cardiac death"..."This result is unexplained; it may arise from risk compensation or some other effect on patients' or doctors' behaviour."
      Kindly finish quoting the entire study.
      Again, there's no raw data to indicate the composition of the fish oils, whether they were pharma grade and what the DHA/EPA content was. It's the DHA/EPA content that's important -- not the fact that it's a "fish oil".
      There is no evidence that fish oils are "immunosuppressive, hepatotoxic…

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    2. Edward John Fearn

      Hypnotherapist and Naturopath

      In reply to Steve Brown

      Yet paradoxically the previous "Dart 1" study demonstrated clear positive outcomes.

      "2033 men who were recovering from acute myocardial infarction (MI). Those who were advised to eat fatty fish (or who opted to take fish oil capsules instead) had a 29% reduction in all-cause mortality over the following two years compared with those not so advised." (1)

      An overview of Dart 1 and 2 are found in the following abstract;

      (1) http://www.ncbi.nlm.nih.gov/pubmed/16456725

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    3. Steve Brown

      logged in via email @yahoo.com.au

      In reply to Laurie Willberg

      "This result is unexplained"

      Fish oil capsules are heavily oxidized. Unfortunately the researchers in charge of the study seemed ignorant of that.

      http://www.nutraingredients.com/Research/Oxidised-fish-oils-on-market-may-harm-consumer-warns-researcher

      "It's the DHA/EPA content that's important -- not the fact that it's a "fish oil".

      That doesn't make any sense. Fish oil *is* DHA & EPA.

      "There is no evidence that fish oils are "immunosuppressive, hepatotoxic and neurotoxic""

      I already…

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    4. Geoff Russell

      Computer Programmer, Author

      In reply to Steve Brown

      Just wondering Steve, do you ever actually read the studies you post links to?

      Do you even read the abstracts? Or do you have some kind of random pubmed number generator?

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    5. Edward John Fearn

      Hypnotherapist and Naturopath

      In reply to Steve Brown

      No only was Dart 2 considered methodologically poor, this study was not blinded and used capsules containing EPA (eicosapentaenoic acid) rich oil derived from fish, but not fish oil.

      www.ncbi.nlm.nih.gov/pmc/articles/PMC1440660/

      "DART 2 data is seriously limited as patient’s recruitment and monitoring was interrupted for 1 year, long-term compliance was uncertain, and sudden death could not be ascertained in all cases "(1)

      (1) Front Physiol. 2012; 3: 57.

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  10. Emma Barlow

    Research Assistant

    Thanks for this article, very thought provoking. I have to admit that the title outright stating that it is a myth that fish oil is good for heart health does not sit well with me, although it definitely enticed me to read the article so that is a job well done there.
    My main issue with the claim that it is a myth that fish oil is good for heart health concerns the mediator, flow on type effects that fish oils may have on heart health in a more global cardiovascular system perspective. While the…

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    1. Michael Vagg

      Clinical Senior Lecturer at Deakin University School of Medicine & Pain Specialist at Barwon Health

      In reply to Emma Barlow

      I wouldn't disagree Emma. I do think though that having a quarter of the population on the stuff without definite proof of efficacy is not justified. As I mention in the article, there are basic science reasons to think that it should be beneficial to supplement with omega 3's but the current weight of large-scale epidemiological evidence doesn't seem to bear this out. With the size of the meta-analyses involved, the power is more than adequate to detect a linically relevant effect. Even in the more positive systematic reviews over the years, the effect size has been admittedly marginal. I wouldn't stop researching fatty acid metabolism on the basis of these meta-analyses but I will be telling my mum and dad not to bother spending $50 a month on them!

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  11. Geoff Russell

    Computer Programmer, Author

    Amidst all the doubt and dispute, there's a few things beyond dispute:

    1) fish and seafood, in total is about 1% of global calories ... with the rich countries basically eating the lion's share (most of the ocean fish eaten in Australia comes from other people's oceans).

    2) Current levels of fish production are unsustainable.

    3) While there is doubt about the impacts of fish oil on the heart, there is no doubt at all that people eating plant food diets (vegetarians/vegans), on average, have…

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    1. Vanessa Wronski

      Software Developer

      In reply to Geoff Russell

      Hi Geoff,

      I've been supplementing my diet with Opti3 Omega DHA and EPA . Primarily algal oil and is vegan. I've been taking it for brain health although it could well be doing nothing.

      I've never taken fish oil and I've been vegan for a number of years.

      Would you mind offering your recommendation on whether or not I should keep on taking this supplement?

      Thanks

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    2. Patrick Hone

      CEO Fisheries Research and Development Corporation

      In reply to Geoff Russell

      Dear Geoff,

      If you would like to find out the actual science of the Australian Fishing Industry I would be happy to provide any reports, papers or data you require (www.frdc.com.au). The comments you have made about the Australian fishing industry are incorrect.

      Australia's current fish production is sustainable. This has been confirmed by numerous international and Australian studies. A recent report by the David and Lucile Packard Foundation, the Gordon and Betty Moore Foundation, the Oak Foundation and the Walton Family Foundation of the California Environmental Associates’ (http://www.chartingacourse.org/) confirmed that Australia and New Zealand are sustainably fished. This report and others also uses Australia as an example of good fisheries management.

      Regards

      Patrick
      PS I am a fisheries scientist

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    3. Geoff Russell

      Computer Programmer, Author

      In reply to Patrick Hone

      Hi Patrick,

      I was speaking globally, but apologise if the context didn't make that clear. I have no idea if Australian
      fisheries are sustainable at current levels, but I'm pretty sure those levels will not supply even today's Australian fish consumption levels, let alone the doubling of fish intake recommended by the CSIRO Total Wellbeing Diet.
      Australians, like most other rich countries supplement their "sustainable" industries with fish from anywhere they can get a good price. I put the word "sustainable" in quotes because all fisheries managers reckon their fisheries are sustainable until they crash.

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    4. Geoff Russell

      Computer Programmer, Author

      In reply to Vanessa Wronski

      As you say, it could well be doing nothing, but at least the collateral damage of your taking it is probably small.
      My only recommendation for vegans is take B12 (see nutritionfacts.org for detailed dose recommendations), get plenty of exercise (physical and mental) and don't eat (too much!) junk.

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    5. Shirley Pipitone

      Independent social researcher

      In reply to Vanessa Wronski

      This reply is for most of the people commenting above.

      I was under the impression that The Conversation forum was intended to promote intelligent informed debate, not for contributions from people who are not entitled to an opinion (see The Conversation of 5 October 2012). I will be very disappointed if this forum continues to go downhill. If you are not able to provide a rational, reasoned argument for what you write (for example, Sean Lamb, believing in intelligent design is not a rational argument), I suggest you find one of the myriad of other websites where the uninformed can write to their heart's content.

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    6. Andrew Wood

      Dr

      In reply to Shirley Pipitone

      Hear, Hear, Shirley! Ironic really, that those who are not entitled to an opinion, and are irrational, are least well equipped to recognise their failings.

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    7. Emma Anderson

      Artist and Science Junkie

      In reply to Geoff Russell

      Reminds me of the metals industry actually. Let's say all our mines are sustainable and have minimal environmental impact. Unlikely, but bare with me.

      The ore is processed overseas and becomes metals that are reimported for use here. But much more of those metals are used in manufacturing, also overseas, and the goods produced are imported here.

      To determine if our metals industry is sustainable and has a low impact requires looking at the entire supply and production chain. If we are…

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  12. Anthony Kaye

    Retired Vet. Surgeon

    Why on earth anyone (other than vegans) would take fish oil supplements is beyond me. I have a kipper, smoked mackerel or piece of salmon, daily for breakfast.
    Delicious!. Also helps with Vit. D- sadly lacking in the UK's sunless summer this year.
    Never in history has the western world had such massive access to such a variety of nutrition. It may not last!. Far better to argue about how we can continue to do so, never mind spreading it to those who don't have it.

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  13. Alexandra McManus

    Public health practitioner

    My impression of 'Monday's Myth' is that it is meant to spark debate and this one certainly has. I premise these comments with the fact that I lead a research centre in seafood science with one of our main foci to promote the health benefits of seafood consumption (including fish) as part of a healthy diet. This we do based on the overwhelming evidence (over 15,000 peer review studies worldwide) that support regular consumption to provide the essential Omega 3 fatty acids we need but cannot produce…

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    1. Michael Vagg

      Clinical Senior Lecturer at Deakin University School of Medicine & Pain Specialist at Barwon Health

      In reply to Alexandra McManus

      Thanks for this very relevant and thoughtful comment Alexandra.

      As I have stated in the article, I would agree that eating more whole fish is beneficial overall, since it means less red meat and a more varied diet overall.

      Whatever the flaws may be of the JAMA meta-analysis there are 2 others as well, in the Archives of Internal Medicine and the Annals of Internal Medicine which also come to the same conclusion.

      Further large-scale epidemiological studies will have to overcome this weight…

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    2. Sue Ieraci

      Public hospital clinician

      In reply to Alexandra McManus

      How fascinating to read about the Centre of Excellence for Science Seafood & Health (CESSH), whose stated aim is to "conduct research that will directly service the research needs of the seafood industry." I don't recall previously coming across an industry organisation of this nature - these insitutues are generally focussed on an area of health or disease rather than a particular product.

      The Omega 3 centre is another interesting alliance of industries in the food and supplement areas.

      Why are people so suspicious about pharmaceutical companies putting money into research and development but not food or supplement manufacturers? Ideally, with good disclosure, we should be able to rely on the quality of the science.

      In the long run, I agree that a focus on a healthy and balanced diet is ideal - without fads or extremes.

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  14. Sue Ieraci

    Public hospital clinician

    The world of lipids - like diet in general, is a fertile field for extremism and whacky theories.

    The problem isn't so much that new evidence emerges (as is the nature of science) but that people forget how multi-factorial health and well-being are.

    So, for example, people might take fish oil capsules, in the hope of improving heart health, but still smoke cigarettes. They might cut out "carbs", or fructose, but not exercise.

    IN the end, it comes down to balance. Some lipids are better than others, some meats are better than others, fresh foods are better than manufactured ones, whole fruits are better than juices - but none of the manufactured products are "toxic" - unless used in excess or out of balance. At the same time, none of hte "nutritional products" are magical.

    Sorry folks, no simple answers here - except perhaps "don't smoke".

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    1. Robert Peers

      General Practitioner

      In reply to Sue Ieraci

      To Sue: I have studied dietary fatty acids--both polyunsaturated [PUFA] and saturated [SAT]--for 22 years, and there is good evidence that low dietary PUF/SAT Ratio [P/S Ratio] causes faulty, PUFA-depleted cell membranes, including mitochondrial membranes. The result is insulin resistance, accompanied by respiratory uncoupling [itself causing energy depletion and free radical excess]. The free radical, superoxide, forms hydrogen peroxide, and these oxyradicals drive low-grade inflammation [e.g. in…

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  15. aric rubin

    logged in via Twitter

    Not all oils are the same. That’s the best suggestion you can take with you when looking for healthy oils/fats to incorporate to your diet. But hold on one minute…why would anyone wish to incorporate more fats to their diet? Well, we know the food we eat affects our body diversely and healthy fats are in fact brain food, affecting your brain’s general tone, degree of energy, and how it handles tasks. Your mind is a hungry organ and can begin to falter without its daily consumption of healthy fats. Intellectual performance requires these fats, primarily omega-3 fatty acids, because they are crucial components of the outer membrane of cognitive abilities. Flaxseed oil may be the richest plant supply of omega-3 fatty acids (and also contains omega-6 fatty acids), is really a polyunsaturated <a href="http://oils.healthfoodxdrinks.com/heart-healthy-oils-fats/"heart healthy oil</a>, and is essential for normal growth and development.

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  16. aric rubin

    logged in via Twitter

    Not all oils are the same. That’s the best suggestion you can take with you when looking for healthy oils/fats to incorporate to your diet. But hold on one minute…why would anyone wish to incorporate more fats to their diet? Well, we know the food we eat affects our body diversely and healthy fats are in fact brain food, affecting your brain’s general tone, degree of energy, and how it handles tasks. Your mind is a hungry organ and can begin to falter without its daily consumption of healthy fats. Intellectual performance requires these fats, primarily omega-3 fatty acids, because they are crucial components of the outer membrane of cognitive abilities. Flaxseed oil may be the richest plant supply of omega-3 fatty acids (and also contains omega-6 fatty acids), is really a polyunsaturated oil, and is essential for normal growth and development. http://oils.healthfoodxdrinks.com/heart-healthy-oils-fats/

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