Selecting Seafood for Health and Sustainability | The Paleo Diet®
noun_Search_345985 Created with Sketch.

Try The Paleo Diet®!

Learn more. Get recipes & meal plans. See the science.

Selecting Seafood for Health and Sustainability

By The Paleo Diet Team
September 12, 2014
Selecting Seafood for Health and Sustainability image

There’s no question that seafood is a great source of protein and omega-3 fatty acids, and that it should form an integral part of the Paleo Diet. But seafood doesn’t thrive in polluted waters, overfished waters, or in habitats damaged by fishing gear. So to get the good without the bad—and to ensure we have it for years to come—we need to know which species have the holy trinity of seafood: sustainable, safe, and nutritious.

Sustainable

Sustainably caught fish may seem like a nice-to-have, but it should really be on par with nutrition for importance when selecting seafood. Not only do we want our food to be harvested or caught in its highest nutritive state, we want that to continue indefinitely. It hasn’t always been that way, but more and more fisheries are making sustainability a reality by considering the health of ecosystems and fish populations as well as their profits. Seafood Watch® makes science-based recommendations for sustainable seafood.1,2,3 Here’s their current list of best choices, good alternatives, and choices to avoid.

Selecting Seafood for Health and Sustainability image

The seafood recommendations in this guide are credited to the Monterey Bay Aquarium Foundation ©2014. All rights reserved.

Download the PDF

Safe

In the seafood world, mercury, dioxins, and PCBs are the usual suspects when it comes to contamination. They’re not normally features of a “healthy and abundant stock” which is a fundamental criterion for sustainability1—so if you’re choosing sustainable, you’re likely choosing safe too. In addition, Seafood Watch® posts health alerts if there are specific concerns for human health from a fishery.

Mercury, however, is a changing story. Mercury accumulates in fat tissues of large, long-lived predatory fish or shellfish, ultimately ending up on our dinner plates. We’ve been cautioned to limit these species in our diets, but surprisingly, that’s not the whole story. Mercury readily and irreversibly binds to selenium,4 which means that as long as the fish you’re eating has more selenium than mercury, your body won’t actually be retaining the mercury you ingest. And since the oceans are full of selenium, most ocean fish are perfectly safe to eat.5,6 Simply avoid shark and limit swordfish, tile fish, and king mackerel or use this infographic to moderate your consumption . Also keep in mind that in freshwater, mercury and selenium levels vary greatly with the composition of the surrounding soil. Check with your local authorities for health alerts.

Nutritious

Fish are great sources of vitamins and minerals as well as protein, but the biggest benefit from eating fish is the omega-3 fatty acids EPA and DHA.7 Anyone who’s had king salmon and a haddock fillet can tell you, however, that all fish are not created equal when it comes to fat—and they’re not all created equal when it comes to omega-3 to omega-6 ratios either—and that matters! Here’s some nutritional data from the USDA for some popular fish and shellfish.6

Selecting Seafood for Health and Sustainability image
Selecting Seafood for Health and Sustainability image

Highlighted numbers in the first four columns are amounts greater than 1 g/100 g; highlighted numbers in the last column are the fish with ratios greater than 5. A few things jump out.

  • Total fat isn’t everything: the number of fish hitting 1 g/100 g decreases as we move from total fat to polyunsaturated fat to omega-3s.
  • Atlantic mackerel, chinook salmon, herring, swordfish, and Bluefin tuna have high total fat and great omega-3/omega-6 ratios.
  • Only farmed Atlantic salmon has more than 1 g/100 g of omega-6s.
  • All but tilapia have an omega-3/omega-6 ratio greater than 1.
  • There doesn’t seem to be a relationship between total fat and the omega-3/omega-6 ratio. There are high fat options with low ratios (Atlantic salmon) and high ratio options with lower fat (squid).

Sustainable + Safe + Nutritious

So can we have our fish and eat it too? Yes! There is an impressively wide array of sustainable options to choose from, and we can assume that they’re safe choices, not only because they’re sustainable, but because they’re high in selenium. Many of those sustainable options are also fatty fish with great omega-3/omega-6 ratios (anything above 1 is great). Seafood Watch® compiled their “Super Green List” based on these criteria, but let’s look at the poor performers to compare.

  • Atlantic salmon: not sustainably caught, high omega-6s, ratio close to 1
  • Bluefin tuna: great fat profile, great ratio, but not sustainable
  • Tilapia: sustainably farmed, but lower in fat, ratio less than 1
  • Sharks: more mercury than selenium, not sustainably caught

The bottom line: while some seafood looks good in the nutritional breakdown, from a sustainability standpoint, some species may be better than others. So, eat your recommended portion of omega-3s, but choose options that tick all the boxes for your health as well as the ocean’s.

Selecting Seafood for Health and Sustainability image

Andrea Moore has dipped her toes in a lot of ponds, lakes, and oceans over the years. She has adventured around the world doing odd jobs and studying biology, languages, and sailing.

Now surprisingly settled in Halifax, Nova Scotia, Andrea’s still up to a bit of everything as a marine biologist, a writer, and an editor, living the Paleo lifestyle.

Selecting Seafood for Health and Sustainability image

Fix.com is a lifestyle blog devoted to bringing you expert content to make your life easier. From products, to food, to fishing, to projects, we’ll be providing you with a daily fix of content from our experienced and knowledgeable team of writers.

References

1. Monterey Bay Aquarium. Developing Seafood Watch® Recommendations. Version: January 23, 2014.

2. Monterey Bay Aquarium. Seafood Watch® Criteria for Aquaculture. Accessed: September 5, 2014.

3. Monterey Bay Aquarium. Seafood Watch ® Criteria for Fisheries. Version: March 31, 2014.

4. Ralston NVC, Ralston CR, Blackwell 3rd JL, Raymond LJ. Dietary and tissue selenium in relation to methylmercury toxicity. NeuroToxicology 2008;29(5):802-11.

5. U.S. Department of Agriculture and U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2010. 7th Edition, Washington, DC: U.S. Government Printing Office, December 2010.

6. US Department of Agriculture, Agricultural Research Service, Nutrient Data Laboratory. USDA National Nutrient Database for Standard Reference, Release 27. Version Current: August 2014.

7. Kidd PM. Omega-3 DHA and EPA for cognition, behavior, and mood: clinical findings and structural-functional synergies with cell membrane phospholipids. Altern Med Rev 2007;12(3):207-27.

Even More Articles For You

Paleo Lifestyle - Consider Bison for Clean, Sustainable Protein
Are you looking for ways to improve the quality of your meat consumption? In this article, learn about how bison is healthier to other meats.
By The Paleo Diet® Team
Dr. Cordain's Response to ABC News' "Caveman Diet Gets Online Support"
Learn how to find the medium between best and reality on the modern Paleo Diet. Visit our website for the best Paleo recipes, diet tips, foods & more.
By Loren Cordain, Ph.D.
Vitamin E: The Paleo Perspective
Symptoms of vitamin E deficiency are rare, but according to at least four national surveys, most Americans consume less than the RDA of this vital nutrient.
By Christopher Clark
Paleo Leadership
 
Trevor Connor
Trevor Connor

Dr. Loren Cordain’s final graduate student, Trevor Connor, M.S., brings more than a decade of nutrition and physiology expertise to spearhead the new Paleo Diet team.

Mark J Smith
Dr. Mark Smith

One of the original members of the Paleo movement, Mark J. Smith, Ph.D., has spent nearly 30 years advocating for the benefits of Paleo nutrition.

Nell Stephenson
Nell Stephenson

Ironman athlete, mom, author, and nutrition blogger Nell Stephenson has been an influential member of the Paleo movement for over a decade.

Loren Cordain
Dr. Loren Cordain

As a professor at Colorado State University, Dr. Loren Cordain developed The Paleo Diet® through decades of research and collaboration with fellow scientists around the world.