What's consumed in America is mostly FARMED tilapia. Farmed fish are fed corn and soy. Since when do fish eat corn and soy? Aren't fish supposed to eat plants and wild algae? Well just like conventionally raised meats, this improper feeding alters the animal's fatty acid ratio. We want to eat animal foods with high Omega-3 levels and low Omega-6 levels (as low as possible). Omega-6 fatty acids create inflammatory conditions in the human body. Farm-raised fish, Tilapia particularly, have highly levels of Omega-6 fatty acids and VERY low Omega-3 fatty acids. This makes farm-raised fish a bad choice.
“It may look like fish and taste like fish but does not have the benefits — it may be detrimental,” said Dr. Floyd Chilton, a professor of physiology and pharmacology at Wake Forest Baptist Medical Center who specializes in fish lipids.
Besides the impact on our health, the farming of this fish is also "damaging ecosystems in poor countries with practices generally prohibited in the United States — like breeding huge numbers of fish in cages in natural lakes, where fish waste pollutes the water. “We wouldn’t allow tilapia to be farmed in the United States the way they are farmed here, so why are we willing to eat them?” said Dr. Jeffrey McCrary, an American fish biologist who works in Nicaragua. “We are exporting the environmental damage caused by our appetites.”
For more information on why farmed Tilapia is NOT a health food, read this NY Times article.
The author of the article, Elizabeth Rosenthal, followed up the story with a blog entry detailing the origins and treatment of those pretty fresh tilapia filets you see in the market:
"If you ask about the provenance of tilapia at your own market, you may discover what I did: that it was previously frozen and then thawed and put on display among fresh fish. And it was farmed in China. How can it look so good after that kind of journey? Much of the tilapia farmed in China is frozen and then treated with carbon monoxide, a gas that prevents meat and seafood from discoloring as it ages. When it is thawed, it looks like new".
So just because your favorite health/fitness magazine or blog recommends a recipe featuring farmed Tilapia - choose another bland white WILD fish instead. :) Eat fish that eat their natural diet of plants and algae instead of corn and soy.