Researchers at the Wake Forest University School of Medicine have found that farm-raised tilapia, one of the most highly consumed fish in America, has very low levels of beneficial omega-3 fatty acids and, perhaps worse, very high levels of omega-6 fatty acids.
According to researchers, the combination could be a potentially dangerous food source for some patients with heart disease, arthritis, asthma and other allergic and autoimmune diseases that are particularly vulnerable to an 'exaggerated inflammatory response.'
Inflammation is known to cause damage to blood vessels, the heart, lung and joint tissues, skin, and the digestive tract.
Researchers said that their research revealed that farm-raised tilapias, as well as farmed catfish, 'have several fatty acid characteristics that would generally be considered by the scientific community as detrimental.'
Tilapia has higher levels of potentially detrimental long-chain omega-6 fatty acids than 80-percent-lean hamburger, doughnuts and even pork bacon, the article says.
"For individuals who are eating fish as a method to control inflammatory diseases such as heart disease, it is clear from these numbers that tilapia is not a good choice," the authors said.
"All other nutritional content aside, the inflammatory potential of hamburger and pork bacon is lower than the average serving of farmed tilapia," they added.
For their study, researchers obtained a variety of fish from several sources, including seafood distributors that supply restaurants and supermarkets, two South American companies, fish farms in several countries, and supermarkets in four states.
All samples were snap-frozen for preservation pending analysis, which was performed with gas chromatography.
The researchers found that farmed tilapia contained only modest amounts of omega-3 fatty acids - less than half a gram per 100 grams of fish, similar to flounder and swordfish.
Farmed salmon and trout, by contrast, had nearly 3 and 4 grams, respectively.
At the same time, the tilapia had much higher amounts of omega-6 acids generally and AA specifically than both salmon and trout.
The study is published this month in the Journal of the American Dietetic Association.