tag:theconversation.com,2011:/fr/topics/edible-algae-41557/articlesEdible algae – The Conversation2017-12-21T14:20:18Ztag:theconversation.com,2011:article/892622017-12-21T14:20:18Z2017-12-21T14:20:18ZCreating a sustainable future: 5 essential reads<figure><img src="https://images.theconversation.com/files/199482/original/file-20171215-17863-17ib8m.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Even pocket parks in cities (Duane Park in Lower Manhattan, pictured here) can shelter wildlife. Read below for ideas about urban biodiversity and other green innovations.</span> <span class="attribution"><a class="source" href="https://upload.wikimedia.org/wikipedia/commons/e/ec/Tribeca_duane_park.jpg">Aude</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span></figcaption></figure><p>Much news about the environment in 2017 focused on controversies over Trump administration actions, such as proposals to promote more use of coal and budget cuts at relevant federal agencies. At the same time, however, many scholars across the United States are pursuing innovations that could help create a more sustainable world. Here we spotlight five examples from our 2017 archives.</p>
<h2>1. Restoring the Rio Grande</h2>
<p>Although many Americans may not realize it, the United States and Mexico work together on many environmental issues along their joint border, including drinking water, sanitation and flood control. Gabriel Diaz Montemayor, assistant professor of landscape architecture at the University of Texas at Austin, <a href="https://theconversation.com/heres-a-better-vision-for-the-us-mexico-border-make-the-rio-grande-grand-again-73111">proposes a bolder vision</a>: greening the entire Rio Grande Valley, which forms more than half of the border. </p>
<p>Restoring vegetation along the river and creating more green space along both sides would help improve river flow and water quality, Montemayor writes. And it could make the border region an attraction that brings Mexicans and Americans together: </p>
<blockquote>
<p>“As the Rio Grande advances to the Gulf of Mexico, it cuts through incredibly valuable, beautiful and remote landscapes, including Big Bend National Park in Texas and the Cañon de Santa Elena, Ocampo, and Maderas del Carmen reserves in Mexico. Traveling its length could become a trip comparable to hiking the Appalachian Trail, with opportunities to see recovering natural areas and wildlife and learn from two of the world’s richest cultures.”</p>
</blockquote>
<figure class="align-right zoomable">
<a href="https://images.theconversation.com/files/199488/original/file-20171215-17842-11454hj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/199488/original/file-20171215-17842-11454hj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=237&fit=clip" srcset="https://images.theconversation.com/files/199488/original/file-20171215-17842-11454hj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=852&fit=crop&dpr=1 600w, https://images.theconversation.com/files/199488/original/file-20171215-17842-11454hj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=852&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/199488/original/file-20171215-17842-11454hj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=852&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/199488/original/file-20171215-17842-11454hj.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=1071&fit=crop&dpr=1 754w, https://images.theconversation.com/files/199488/original/file-20171215-17842-11454hj.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=1071&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/199488/original/file-20171215-17842-11454hj.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=1071&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">View of Tule Canyon and the Rio Grande from Burro Bluff, Big Bend National Park.</span>
<span class="attribution"><a class="source" href="https://www.nps.gov/rigr/planyourvisit/lower_cyns.htm">National Park Service</a></span>
</figcaption>
</figure>
<h2>2. Making jet fuel from sugarcane</h2>
<p>Jet airplane travel is one of the world’s fastest-growing greenhouse gas emissions sources. For this and other reasons, including concerns about oil price spikes, there is growing interest in producing jet fuel from nonpetroleum sources. </p>
<p>Researchers at the University of Illinois are working on making <a href="https://theconversation.com/jet-fuel-from-sugarcane-its-not-a-flight-of-fancy-84493">jet fuel from sugarcane</a>, an abundant and low-cost source. But they are doing it with a twist. Instead of fermenting cane juice into an alcohol-based fuel, as Brazil already does for motor vehicles, they have engineered the cane to produce oil that can be used to make biodiesel. </p>
<p>This engineered version, which they call lipidcane, could become a lucrative crop. “We calculate that growing lipidcane containing 20 percent oil would be five times more profitable per acre than soybeans, the main feedstock currently used to make biodiesel in the United States, and twice as profitable per acre as corn,” the authors write. They also are engineering it to be more cold tolerant so that it can be grown on marginal land in the southeastern United States. </p>
<h1>3. A legal right to a clean environment</h1>
<p>Are all humans <a href="https://theconversation.com/is-a-healthy-environment-a-human-right-testing-the-idea-in-appalachia-80372">entitled to live in a clean and healthy environment</a>? West Virginia University legal researcher Nicholas Stump and his colleagues are exploring this proposal in a challenging setting: Appalachia, where mining and logging have severely damaged the environment and polluted the air, water and soil. Appalachia is well-suited for a bottom-up, critically informed approach that focuses on human rights at the grassroots level, he writes:</p>
<blockquote>
<p>“Discussing rights at the local level will give people opportunity to describe specific harms they have experienced from activities such as mountaintop removal and fracking. It also will help to promote participatory democracy for citizens who have long been denied real self-determination.”</p>
</blockquote>
<p>This work is part of West Virginia University’s new <a href="https://aji.law.wvu.edu/home">Appalachian Justice Initiative</a>, which will include research, advocacy and direct legal services and outreach to Appalachian communities. “Our goal is to help people in our region call for laws and actions that actually guarantee the right to a healthy Appalachian environment,” Stump explains.</p>
<figure>
<iframe src="https://player.vimeo.com/video/66179035" width="500" height="281" frameborder="0" webkitallowfullscreen="" mozallowfullscreen="" allowfullscreen=""></iframe>
<figcaption><span class="caption">Appalachia residents protest mountaintop removal coal mining in Washington DC, May 8, 2013.</span></figcaption>
</figure>
<h1>4. Stemming world hunger with marine microalgae</h1>
<p>Feeding a growing world population sustainably in the coming decades will be a major environmental challenge. Large-scale farm production pollutes air and water, generates greenhouse gas emissions and degrades soil. </p>
<p>William Moomaw, professor of international environmental policy at Tufts University, and Asaf Tzachor, a Ph.D. candidate at University College London, see marine microalgae as <a href="https://theconversation.com/micro-solutions-for-a-macro-problem-how-marine-algae-could-help-feed-the-world-85702">a key untapped resource</a>. These tiny organisms live in fresh and salt water, and form the base of marine food chains. They are the sources of the omega-3 fatty acids and amino acids that humans get by eating fish. Moomaw and Tzachor call for “cutting out the middle fish” and developing foods based directly on microalgae.</p>
<p>“Most algae-based products are marketed in the United States as dietary supplements, but we believe the time has arrived to introduce algae-based foods to the dining table,” they write.</p>
<p>Microalgae can be grown in open ponds or sealed tubes in a laboratory. Moomaw and Tzachor calculate that producing one kilogram of beef-sourced essential amino acids would require 148,000 liters of freshwater and 125 square meters of fertile land. In contrast, producing the same amount from an omega-3 rich microalgae called <em>Nannochloropsis oculata</em>, raised in an open pond with brackish water, would require only 20 liters of freshwater and 1.6 square meters of nonfertile land.</p>
<figure class="align-center zoomable">
<a href="https://images.theconversation.com/files/199490/original/file-20171215-17848-g7ghjp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=1000&fit=clip"><img alt="" src="https://images.theconversation.com/files/199490/original/file-20171215-17848-g7ghjp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/199490/original/file-20171215-17848-g7ghjp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=422&fit=crop&dpr=1 600w, https://images.theconversation.com/files/199490/original/file-20171215-17848-g7ghjp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=422&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/199490/original/file-20171215-17848-g7ghjp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=422&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/199490/original/file-20171215-17848-g7ghjp.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=530&fit=crop&dpr=1 754w, https://images.theconversation.com/files/199490/original/file-20171215-17848-g7ghjp.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=530&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/199490/original/file-20171215-17848-g7ghjp.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=530&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px"></a>
<figcaption>
<span class="caption">Growing algae indoors in photobioreactors conserves land and water.</span>
<span class="attribution"><a class="source" href="https://upload.wikimedia.org/wikipedia/commons/b/ba/Photobioreactor_PBR_4000_G_IGV_Biotech.jpg">IGV Biotech</a>, <a class="license" href="http://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA</a></span>
</figcaption>
</figure>
<h1>5. Understanding biodiversity in cities</h1>
<p>Sustainable strategies for the future don’t have to be technically complex or sweeping. Geographer Christopher Swan of the University of Maryland, Baltimore County, studies biodiversity in parks, backyards and other natural areas around the city of Baltimore. Swan wants to see <a href="https://theconversation.com/urban-nature-what-kinds-of-plants-and-wildlife-flourish-in-cities-71680">what species thrive in cities</a> and how human activities affect them.</p>
<p>As urban dwellers build and remodel houses and develop neighborhoods, they divide urban space into small units with many edges, Swan has found: </p>
<blockquote>
<p>“This benefits species that thrive at edges, like white-tailed deer and nuisance vines, but harms others that require larger interior habitats, such as certain birds. As human activities create a more fragmented environment, it becomes increasingly important to create linkages between natural areas, such as preserved forests, to maintain populations and their biodiversity.”</p>
</blockquote>
<p>Humans also move species around: They bring plants into their yard, and trap and remove nuisance animals such as squirrels.</p>
<p>Swan is working with his students to identify native plant species that can thrive in poor urban soils, and to identify species traits – such as offering habitat for pollinating insects – that can make species valuable in urban settings. With information like this, city managers can restore and support urban wildlife, making cities more inviting places to live.</p><img src="https://counter.theconversation.com/content/89262/count.gif" alt="The Conversation" width="1" height="1" />
Trump administration rollbacks dominated news about the environment in 2017 – but beyond Washington D.C., many researchers are developing innovative visions for a greener future.Jennifer Weeks, Senior Environment + Cities Editor, The ConversationLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/889802017-12-14T11:07:59Z2017-12-14T11:07:59ZPutting algae and seaweed on the menu could help save our seafood<figure><img src="https://images.theconversation.com/files/199053/original/file-20171213-27593-sfv3nk.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">
</span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>If we have to feed <a href="https://www.un.org/development/desa/en/news/population/world-population-prospects-2017.html">9.8 billion people</a> by 2050, food from the ocean will have to play a major role. Ending hunger and malnutrition while meeting the demand for more meat and fish as the world grows richer will require <a href="http://www.fao.org/fileadmin/templates/wsfs/docs/expert_paper/How_to_Feed_the_World_in_2050.pdf">60% more food</a> by the middle of the century.</p>
<p>But <a href="https://www.theguardian.com/environment/2016/jul/07/global-fish-production-approaching-sustainable-limit-un-warns?CMP=share_btn_tw">around 90%</a> of the world’s fish stocks are already seriously depleted. Pollution and increasing levels of carbon dioxide (CO₂) in the atmosphere, which is making the oceans warmer and more acidic, are also a significant threat to marine life.</p>
<p>There is potential to increase ocean food production but, under these conditions, eating more of the species at the top of the food chain, such as tuna and salmon, is just not sustainable. As a <a href="https://www.sapea.info/wp-content/uploads/FFOFINALREPORT.pdf">recent EU report</a> highlighted, we should instead be looking at how we can harvest more smaller fish and shellfish, but also species that aren’t as widely eaten such as seaweed and other algae.</p>
<p>The oceans have absorbed <a href="https://cloudfront.escholarship.org/dist/prd/content/qt8r14828w/qt8r14828w.pdf">around one third</a> of the CO₂ emitted into the atmosphere since the Industrial Revolution. The absorbed CO₂ goes through a series of chemical reactions that form carbonic acid and <a href="https://theconversation.com/global-warmings-evil-twin-ocean-acidification-19017">lower the pH of the water</a>. These reactions also reduce the concentration of carbonate ions, which are vital for those creatures that grow external skeletons such as corals and shellfish.</p>
<p>The acid and the lack of carbonate mean these organisms <a href="https://phys.org/news/2016-02-ocean-acidification-coralline-algae-robust.html">form weaker skeletons</a> and have to use more energy to do so, leaving less energy for growth and reproduction. Consequently, they up smaller in size. Aside from the <a href="https://theconversation.com/mussel-power-how-ocean-acidification-is-changing-shells-54976">impact this has on shellfish</a>, several of the species affected, such as corals in the tropics or <a href="https://www.nature.com/articles/srep20572">coralline algae</a> in the waters around the UK, also play a key role in providing food and nursing grounds for fish. And less fish food leads to fewer fish for us to catch.</p>
<h2>Climate change is affecting food production</h2>
<p>The impact of ocean acidification <a href="http://ec.europa.eu/research/sam/pdf/topics/food_ocean_sapea_report.pdf">varies widely across the globe</a>. But it is already affecting marine food production, particularly of shellfish. For example, CO₂-rich water along the west coast of the US means more oysters in local hatcheries are dying when <a href="http://tos.org/oceanography/article/impacts-of-coastal-acidification-on-the-pacific-northwest-shellfish-industr">they are still larvae</a>.</p>
<p>Warmer seas due to climate change are also affecting food supplies. Some species are <a href="https://www.theguardian.com/environment/2017/jan/08/fish-ocean-warming-migration-sea">moving towards the poles</a> in search of cooler water, forcing fishermen into more northerly waters or leaving them without stocks altogether. Some fishing fleets in northern locations will find more fish available but many will see the amount of fish available to catch fall by between <a href="https://www.nature.com/news/nutrition-fall-in-fish-catch-threatens-human-health-1.20074">6% and 30% depending on the region</a>. The biggest impact will be on areas that are already the most dependent on fishing, such as <a href="https://link.springer.com/article/10.1007/s11160-013-9326-6">Southeast Asia and West Africa</a>. </p>
<p>One possible solution is to eat more smaller fish and shellfish such as mussels. Large fish need to eat smaller fish to grow. If we eat smaller fish instead then we remove a step from the food chain and reduce the amount of energy lost in the process. What’s more, it might become easier to farm these smaller fish because the algae, cyanobacteria and other plankton they eat could actually benefit from warmer waters and higher levels of CO₂ in the atmosphere. This is because they get their energy from <a href="http://www.open.edu/openlearn/science-maths-technology/across-the-sciences/sunlight-powered-food-key-life-on-earth">photosynthesis</a> and so <a href="https://www.ncbi.nlm.nih.gov/pubmed/19093090">use CO₂ like fuel</a>.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/199054/original/file-20171213-27575-1vq58v9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/199054/original/file-20171213-27575-1vq58v9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/199054/original/file-20171213-27575-1vq58v9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/199054/original/file-20171213-27575-1vq58v9.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/199054/original/file-20171213-27575-1vq58v9.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/199054/original/file-20171213-27575-1vq58v9.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/199054/original/file-20171213-27575-1vq58v9.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">Spirulina, the new seafood cocktail.</span>
<span class="attribution"><span class="source">Shutterstock</span></span>
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</figure>
<p>It might also be possible to take this a step further and add some of these organisms directly to our diet, giving us an abundant new source of food. Seaweed, for example, is a type of algae that has been eaten for centuries, but only <a href="http://www.fao.org/docrep/006/y4765e/y4765e04.htm">35 countries commercially harvest</a> it today. Spirulina cyanobacteria is already eaten as a food supplement and <a href="http://www.independent.co.uk/life-style/food-and-drink/first-algae-based-vegan-eggs-holland-and-barrett-caked-omlettes-scrambled-eggs-plant-based-a7543901.html">several companies</a> are trying to turn other forms of algae into a <a href="https://link.springer.com/article/10.1007/s10811-016-0974-5">human food source</a>.</p>
<p>Farming these organisms in the right way could even help counter some of the effects of climate change on the rest of the food chain. For example, growing more seaweed <a href="https://www.greenwave.org/">lowers the amount of CO2</a> in the surrounding water, reduces acidification, and improves the environment for oysters and other shellfish. Managing seaweed harvest correctly will also maintain the dissolved oxygen and nutrient levels in the water, contributing to the overall health of the ocean.</p>
<p>Making algae a common part of more people’s diets won’t be easy. We need to ensure that any new algae food products on our dinner plates have the needed nutritional value but are also attractive and safe to eat. But sticking with our traditional salmon and tuna diet isn’t sustainable. Expanding our seafood menus could be a vital way of keeping the ocean healthy while it supplies the food we need.</p><img src="https://counter.theconversation.com/content/88980/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Pallavi Anand receives funding from the UK Ocean Acidification research programme of Natural Environment Research Council and the Cushman Foundation for Foraminiferal research. </span></em></p><p class="fine-print"><em><span>Daniela Schmidt receives funding from the Natural Environment Research Council of the UK and the Royal Society (UK)</span></em></p>The ocean is getting warmer and more acidic but changing our diet could help us cope.Pallavi Anand, Lecturer in Ocean Biogeochemistry, The Open UniversityDaniela Schmidt, Professor in Palaebiology, University of BristolLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/820222017-08-04T10:16:30Z2017-08-04T10:16:30ZDo we really face a human fertility cliff-edge? Science offers hope<figure><img src="https://images.theconversation.com/files/180863/original/file-20170803-7693-18snuuc.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Spirulina is a blue-green algae with multiple uses.</span> <span class="attribution"><a class="source" href="https://www.shutterstock.com/image-photo/spirulina-powder-688920580?src=vOY2DY79bjVxJ3clJBhYbA-1-0">Shutterstock</a></span></figcaption></figure><p>A friend recently confided in me about his fertility problems. His physician had told him his sperm were small and malformed, to the point that he might struggle to get his wife pregnant. In an effort to make him feel less bad, perhaps, she added that male fertility problems were currently at “epidemic” levels in the UK.</p>
<p>Recent articles in several major news outlets told this same worrisome tale. For instance, one BBC <a href="http://www.bbc.co.uk/news/health-40719743">headline screamed</a>, “sperm count drop ‘could make humans extinct’”. These articles were based on <a href="https://academic.oup.com/DocumentLibrary/humupd/PR/dmx022_final.pdf">authoritative new research</a> that found a large and continuing fall in sperm count across numerous countries, as also <a href="https://theconversation.com/huge-drop-in-mens-sperm-levels-confirmed-by-new-study-here-are-the-facts-81582">reported in The Conversation</a>. </p>
<p>Under current trends, this could lead to human males being largely infertile by 2060, with exposure to toxic chemicals and unhealthy lifestyles thought to be the main causes. As if there weren’t already enough problems in the world, what with geopolitical tensions and issues such as war, poverty and climate change …</p>
<p>So are we doomed? Well, there may be cause for optimism.</p>
<p>Various natural remedies are touted as ways to increase men’s sperm count by the <a href="http://www.telegraph.co.uk/health-fitness/body/increase-sperm-count/">popular press</a>, <a href="http://natural-fertility-info.com/">fertility websites</a> and <a href="http://low-sperm-count.com/blog/boost-amount-sperm-quality/">blogs</a>. Examples include eating healthy foods, exercising regularly, and limiting time spent at a computer.</p>
<p>I cannot comment on such claims. I can, however, share relevant insights from <a href="http://www.uea.ac.uk/international-development/people/profile/j-siedenburg#researchTab">my own work</a>, which involves researching algae and its potential to help poor communities in the global South meet their food needs. While I focus on algae as a food, it also has various other uses, such as animal feed, pharmaceutical applications, and energy production. Given the headlines about infertility, I wanted to report what researchers have learned about edible algae (notably <a href="https://link.springer.com/article/10.1007/s00204-016-1744-5">spirulina</a>) and its linkages to fertility.</p>
<h2>What the science says</h2>
<p>One way to assess any new health treatment is human trials, another is to test it with animals. To date, most research on the significance of edible algae to fertility has involved animal studies. Firm conclusions therefore cannot be drawn about the applicability of this work to humans. These early studies nonetheless flag linkages that could equally apply to humans.</p>
<p>The available science reveals substantive and sometimes dramatic improvements in male reproductive function thanks to spirulina. The following examples show this effect consistently in a range of different contexts, as reported in peer-reviewed academic papers by researchers from institutions such as the University of Cairo, the University of Tasmania and Mexico’s National Polytechnic Institute.</p>
<figure class="align-center ">
<img alt="" src="https://images.theconversation.com/files/180864/original/file-20170803-5614-491f9l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/180864/original/file-20170803-5614-491f9l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=400&fit=crop&dpr=1 600w, https://images.theconversation.com/files/180864/original/file-20170803-5614-491f9l.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=400&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/180864/original/file-20170803-5614-491f9l.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=400&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/180864/original/file-20170803-5614-491f9l.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=503&fit=crop&dpr=1 754w, https://images.theconversation.com/files/180864/original/file-20170803-5614-491f9l.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=503&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/180864/original/file-20170803-5614-491f9l.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">Could algae supercharge human fertility?</span>
<span class="attribution"><a class="source" href="https://www.shutterstock.com/download/success?src=9tCVc4VoGGBSEuX0mvk_Fw-1-4">Shutterstock</a></span>
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<p>One group of studies involved different animals of importance to agriculture. For instance, two studies found enhanced male reproductive function <a href="https://www.academia.edu/4392666/Effect_of_the_spirulina_platensis_included_in_the_main_diet_on_the_boar_sperm_quality">for</a> <a href="http://dspace.uasm.md/handle/123456789/1726">boar</a> when spirulina was incorporated into their feed, while a third found this same effect for <a href="https://www.cabdirect.org/cabdirect/abstract/20083149887">bulls</a>. </p>
<p>Similarly, studies on fish found higher fertility and larger gonad size among farmed <a href="http://evols.library.manoa.hawaii.edu/handle/10524/19166">red swordtail</a>, <a href="https://link.springer.com/article/10.1007/s10499-015-9909-4">gourami</a> and <a href="https://link.springer.com/article/10.1007/s10499-012-9512-x">yellow-tailed cichlid</a> when their diet included spirulina.</p>
<p>A second set of studies involved laboratory rodents, and found that spirulina protected their sperm and reproductive organs from various pathogens. For instance, several studies showed this for key industrial toxins, such as <a href="https://pdfs.semanticscholar.org/f2b3/e0fae087454896259d19c960baaca6953298.pdf">mercury</a>, <a href="https://www.hindawi.com/journals/omcl/2016/7174351/abs/">arsenic</a>, and the carcinogen <a href="http://online.liebertpub.com/doi/abs/10.1089/jmf.2013.0109">benzo-alpha pyrene</a>. </p>
<p>Other studies showed spirulina minimising the adverse effects of chemotherapy on testicular function of both <a href="http://www.ejmanager.com/mnstemps/36/36-1393854219.pdf">rats</a> and <a href="http://www.sciencedirect.com/science/article/pii/S0278691507003316?via%3Dihub">mice</a>, while yet another study showed spirulina protecting the reproductive function of male mice from <a href="https://inis.iaea.org/search/searchsinglerecord.aspx?recordsFor=SingleRecord&RN=47091672">gamma radiation</a>.</p>
<p>Several recent reviews of the early research on spirulina are also pertinent. <a href="http://onlinelibrary.wiley.com/doi/10.1111/j.1439-0396.2012.01328.x/full">One</a> covered studies on the potential of spirulina to enhance the health, growth rates and quality characteristics of different agricultural animals. <a href="http://www.tandfonline.com/doi/abs/10.3109/13880209.2015.1077464">Another</a> covered experiments on the capacity of spirulina to help laboratory animals cope with diverse pollutants and industrial toxins. A <a href="http://www.ingentaconnect.com/content/ben/mrmc/2013/00000013/00000008/art00009">third</a> covered research on the capacity of spirulina to help protect humans from different types of pathogens, including microbes, heavy metals, and cancer. All three review papers were highly positive regarding the impacts of spirulina, while also noting that further research is needed. </p>
<p>Please don’t misunderstand: I am not claiming that eating algae can address humanity’s fertility concerns. The available scientific evidence is limited, and more research is needed to clarify these linkages.</p>
<p>The provisional take home message from the early research is nonetheless clear: various studies give cause for hope that edible algae could significantly boost reproductive function in men, notably where it is threatened by industrial toxins. For me at least, such findings offer one good reason for optimism that a human fertility crisis might be averted.</p><img src="https://counter.theconversation.com/content/82022/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Jules Siedenburg 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>Numerous studies suggest that spirulina could help safeguard fertility.Jules Siedenburg, Research fellow in international development, University of East AngliaLicensed as Creative Commons – attribution, no derivatives.