Pollan, in “The Omnivore’s Dilemma,” mentioned that our impression of salmon as superior to beef as a source of omega 3 fatty acids was based on measurements taken at the time in which we first became conscious of omega 3s. That was when most available beef was corn fed and most salmon was wild. Pollan further claims that grass fed beef is a better source omega 3s than farmed salmon, which is what most consumers eat now.

McGee, in an e-mail reply to my query, said “Farmed salmon are raised primarily on fish meal (which is problematic in its own way)…” I expect him to make more of a statement on his blog regarding this issue, but he also noted that farm salmon probably have a significantly omega-3 level than wild, because they have significantly higher levels of all fats.

It’s a good post and sheds a good deal more light on the subject. It’s as thorough a reply as one would hope to get from him.