Fish is frequently ordered because it is perceived as a health conscious choice. However, very frequently, this is not the case and the situation is only getting worse.

Fish can absolutely be a part of a healthy lifestyle (for you, of course–not the fish…) but there are some details you need to be aware of. 

First is the mercury content of fish. Mercury is one of the most potent neurotoxins on the planet, so keeping our exposure to the smallest levels possible is a good idea (don’t ask me WHY anyone thought it was a good idea to put mercury into amalgam fillings…). Since it is pretty much present everywhere in the environment, including your can of soda (which you shouldn’t actually be drinking) that contains mercury-laden high fructose corn syrup, we need to steer towards fish with lower content of mercury. This means eating younger fish who have not had time to accumulate mercury in their life span (think chunk light tuna instead of the older albacore) and fish that are vegetarian (mercury bioaccumulates, so as each fish gets eaten by another fish, the prey fish’s mercury is added to the predator). The FDA has a great resource for determining which fish are higher in mercury.

The next factor is wild caught vs farm raised. This is probably the largest determining factor you should use in deciding whether or not to eat a particular fish. For a variety of reasons, farmed raised fish should be avoiding in almost all cases. They are higher in pesticide residues, antibiotics and parasites present only in farm raised salmon escape into the wild salmon and actually destroy the wild salmon.

But arguably the largest difference in farm raised vs wild caught in the fats contained in them. In the wild, fish like salmon will eat smaller fish and algae. This is the source of the “fish oils” in wild caught fish. DHA is the ultimate source and comes from marine plant and algae life. But what about farm raised?

I remember having dinner at a small restaurant in Phoenix recently and the chef was present. When I asked whether the salmon was farm raised or wild, he mentioned that he does not like wild caught because the taste can vary.  When I mentioned that we only do wild caught, he went on a mini-tirade talking about how he’s knows FDA inspectors and all the information about the living conditions and antibiotic use and pesticide levels were not true. I mentioned to him that they were fed primarily a corn based diet and he said that wasn’t true. At this point, my dinner mates were telling me to shut up under their collective breaths.

So, apparently, if the chef and restaurant owner does not even understand the difference, you better be that much better informed as the consumer. Yes–they ARE higher in pesticides and other chemicals because they are typically kept in a tighter environment in non-flowing water so they are more likely to rub against one another and create lesions and sores that need to be treated. Yes–they are fed a corn based diet. Even though some of the conditions are changing (Whole Foods carries a line of farmed raised seafood that is unquestionably higher quality, but I still have concerns over the omega-6 content), the safest bet is to avoid farm raised.

Remember that our health is better served by increasing the content of omega-3 fatty acids in our diets and reducing the amount of omega-6 (think corn, sunflower, safflower, soybean, cottonseed, peanut oils) fatty acids in our diets. If farm raised fish are being fed a corn based diet, guess which fatty acid is going to dominate?

This particular article, I fear, may be used to support the use of farm raised fish.  Basically, researchers looked at the omega-3 content of farm raised vs wild caught fish. For starters, the farm raised fish had twice the fat of their wild counterparts, but given their restricted environment, we’d get fat too. Next, they confirmed that a “substantial” amount of the oils from the feed make it into the farm raised fish (not a good thing–after all, are any of the oils named above part of a wild salmon’s diet??). 

BUT, the authors state, the omega-3 content of farm raised was slightly higher than that of the wild caught fish.  Sounds like a great marketing ploy if you just take this line. Consider the entire picture…More chemicals. More excess fat. More omega-6 fatty acids. All on top of the other negative aspects of farm raised fish.

Are you willing to risk your health on the finding that there is a slightly higher omega-3 content over the boatload of negatives?

James Bogash

For more than a decade, Dr. Bogash has stayed current with the medical literature as it relates to physiology, disease prevention and disease management. He uses his knowledge to educate patients, the community and cyberspace on the best way to avoid and / or manage chronic diseases using lifestyle and targeted supplementation.