Not only are Omega-3 fatty acids essential to our bodies’ metabolic processes but they provide a growing list of health benefits. Cancer, heart disease, immune response, and brain health are all positively impacted by Omega-3s. As more research comes out pointing to the large role chronic inflammation plays in many ailments, the importance of Omega-3s has grown in the popular awareness.
Marine life is the sole source for two essential Omega-3s, DHA and EPA. Those who do not eat seafood can synthesize some amounts of DHA and EPA from ALA, which is found in flax seeds. The efficiency of this synthesis process varies by individual but is typically no greater than 5%. Thus, it maybe wise to occasionally consume seafood in order to obtain larger amounts of DHA and EPA. Dr. Weil recommends fish high in Omega-3s at least twice a week.
The problem is many seafood contains dangerous levels of mercury and PCBs. These toxins bioaccumulate meaning even small amounts can build up in the body because they are stored in tissue faster than they are released. While PCBs were banned from US manufacture in 1977 they still persist in the environment. It is stored in the fat and skin so discarding that before cooking can help. Mercury is mainly released from the burning of coal, 150 tons per year in the US alone. Since we have chosen fossil fuels as our primary energy source, mercury in the environment is not going away anytime soon unfortunately. Health risks include neurological and behavior problems as well as kidney and heart disease. Even small amounts can produce negative effects, especially in children whose development can be significantly and permanently altered.
Seafood is one of those areas where government regulations lags. A substantial body of research has compelled various advisories, however a visit to any grocery store or restaurant will reveal these advisories are largely ignored. Grouper, tuna, swordfish, flounder and other species known to have very high amounts of mercury and PCBs are regularly bought and consumed. It is up to consumers to educate themselves.
Using data from the Environmental Defense Fund and the Nutrition Search Engine, I have composed a list of seafood that contain high amounts of beneficial Omega-3 fatty acids while being relatively safe to consume. The source of the fish if specified in parenthesis is important, particularly in the case of mackerel and salmon.
- Cod (Atlantic)*
- Crab (king U.S.)*
- Mackerel (Atlantic)**
- Mussel (blue)**
- Salmon (wild Alaskan)**
** high DHA (500mg or more per 170g serving)
* moderate DHA (200mg – 500mg per 170g serving)