Fish; delicious additions to any omnivore’s dinner plate (assuming you don’t have an allergy or something). But which ones should you eat?
Wild fish should take precedence over farmed fish. Farmed fish tend to contain dioxins, chemical byproducts of pollution, which are associated with birth defects, cancer, and a host of other dreadfully unpleasant health problems. PCB’s are another wonderful chemical which can cause liver failure and endocrine disruption and are present in most fish, but to varying degrees. They are almost always much higher in farmed fish, usually 5-10 times higher. Pollutants are almost always higher in farmed fish and that is a solid enough reason to go for the wild varieties. Wild fish are also usually more nutritious, with higher levels of EPA and DHA fatty acids (the two superior omega-3 fatty acids), and lower levels of omega-6 fatty acids (which most people eat too much of). Of course, the issue of what seafood is best goes far beyond the farmed or wild issue; how healthy each particular fish is can vary depending on species.
For the most part, oily fish like salmon, sardines, and anchovies are healthier than “white fish” like cod, pollock, tilapia, and mahi mahi. Most fish offer a good supply of omega-3’s, vitamin D, and Vitamin A, but white fish store these nutrients in their livers and not their flesh (cod liver oil anyone?). Shellfish are also quite healthy and nutritionally dense, but shrimp can contain a fair amount of dangerous chemicals (like PCB and mercury). Finally, fish higher up on the food chain should be avoided or eaten infrequently because they accumulate things like mercury. This includes shark, swordfish, and king mackerel. This is my personal list of most preferable fish (assuming all are from wild sources):
1. Oily fish: salmon, trout, sardines, anchovies, herring, and mackerel (king mackerel excluded). I’m also putting oysters up here and add that there doesn’t seem to be much difference in quality between farmed and wild oysters.
2. Various shellfish and seafood: Clams, lobster, crab, mussels, scallops, and squid/octopus.
3. Tuna (Yellowfin perhaps being the best) and shrimp.
4. Common white fish: Cod, pollock, tilapia, and mahi mahi.
5. Shark, marlin, swordfish, king mackerel.