While the media touts fish as a health food, I've been preaching otherwise for some time now. Besides the Omega-3 fatty acids found in most fish, there's really no benefit to eating it, although there are plenty of hazards: mercury, PCB's (Polychlorinated Biphenals), cholesterol content (the same as red meat), homocysteine levels, Heterocyclic Amines, and of course, fish has no fiber.
The one beneficial compound in fish - Omega 3's - are found throughout plant foods such as nuts, flaxseed and other seeds, legumes, whole grains and fatty fruit like avocados.
But wait, just in case you still weren't convinced, there's a new study published online in the European Journal of Heart Failure (2009;11:922-928) that contradicts the belief that fish prevents heart disease. Researchers studied over 5,000 men and women (who lived in the Netherlands) for over 11 years and compared episodes of heart failure between those who consumed the most fish and those consumed the least. Guess what? They found NO DIFFERENCE. In fact, in their own words, the author of the study concluded: "Our findings do not support a major role for fish intake in the prevention of heart failure."