Researchers at Wake Forest University School of Medicine in Winston-Salem, N.C., say the combination of could be a potentially dangerous food source for some patients with heart disease, arthritis, asthma and other allergic and auto-immune 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, the researchers say.

"In the United States, tilapia has shown the biggest gains in popularity among seafood and this trend is expected to continue as consumption is projected to increase from 1.5 million tons in 2003 to 2.5 million tons by 2010," the researchers say in a statement.

Farm-raised tilapia, as well as farmed catfish, "have several fatty acid characteristics that would generally be considered by the scientific community as detrimental," the researchers sat.

The article, published in the Journal of the American Dietetic Association, says tilapia has higher levels of potentially detrimental long-chain omega-6 fatty acids than 80-percent-lean hamburger, doughnuts and pork bacon.