Dr. Weil's short note warns against eating farm-raised tilapia. It's said that tilapia contains little Omega-3 but a lot of Omega-6, which our bodies already have too much of to strike a balance with Omega-3. He recommends salmon, especially the wild Alaskan type. His comment corroborates with Wikipedia which probably cited this 2008 arcitle. That aritlce says (my bold text), "This analysis revealed that trout and Atlantic salmon contained relatively high concentrations of n-3 PUFA, low n-6:n-3 ratios, and favorable saturated fatty acid plus monounsaturated fatty acid to PUFA ratios. In contrast, tilapia (the fastest growing and most widely farmed fish) and catfish have..."