The Cooper Institute

Founded in 1970 by the "Father of Aerobics"
Kenneth H. Cooper MD, MPH


Promoting Fish Consumption: The Challenges

Posted in
Eat better

Thursday, Jun 05, 2014

The 2010 Dietary Guidelines for Americans advise consumption of 8 ounces of fish per week in order to reach an average daily intake of 250 mg of omega-3 fatty acids1. At present, per capita consumption remains at approximately half of this recommended level. The Dietary Guidelines are based not only on fish being a good source of protein and omega-3 fatty acids, but also on clinical studies associating fish consumption with a reduced risk of coronary artery disease in adults, and with improved neurological outcomes in infants and young children2.

These recommendations are also based on evidence that the health benefits of increased fish consumption outweigh the risks associated with methylmercury, a toxic contaminant of large predatory fish (tilefish, shark, swordfish, and king mackerel). To limit intake of this toxin, the guidelines advise eating fish that is lower in methylmercury, e.g., salmon, anchovies, sardines, and trout3.

In a study conducted by Nielsen et. al, researchers examined whether adhering to current recommendations might raise methylmercury intake above safe amounts. Blood samples collected from adults during the 2007-2010 National Health and Nutrition Examination Survey were analyzed for mercury concentration, and were then compared to the type and frequency of fish consumption. Of the total sample, 4.6% showed blood concentrations above the Environmental Protection Agency’s recommended levels4.

As expected, the study found that the risk of blood mercury concentrations exceeding the reference level was greatest for adults who most frequently consumed shark and swordfish. Risk was lower for salmon and tuna consumption, and did not increase with shrimp and crab consumption4.

Beyond the concern of exceeding recommended doses of methylmercury, the challenges of placing impossible demands on an already threatened fish supply should not be ignored. Currently, many ocean fisheries are either fully exploited or are in decline. Pressures to increase fish consumption in the face of limited supply could potentially price seafood out of the reach of many consumers3.

Promoting the nutritional value of fish, while at the same time considering the potential health risk of contaminants that are found in fish, represents an important health issue. Additionally, cost and the environmental effects of overfishing will be some of the important challenges under consideration as the 2015 Dietary Guidelines for Americans are being developed.

To learn more about the benefits of fish consumption, take The Cooper Institute’s Providing Dietary Guidance course.


1Dietary Guidelines for Americans, 2010. Retrieved May 13, 2014 from US Department of Agriculture: US Department of Health and Human Services website:

2Nesheim, M. (2007). Seafood choices: balancing benefits and risks. Washington, DC: National Academy Press.

3Nesheim, M, Nestle, M. (2014). Advice for fish consumption: challenging dilemnas. American Journal of Clinical Nutrition. 99:973-974.

4Nielsen, S., Kit, B., Aoki, Y., Ogden, C. (2014). Seafood consumption and blood mercury concentrations in adults aged >20 y, 2007-2010. American Journal of Clinical Nutrition. 99:1066-1070.