The Two-Sided Story of Fish Oil

Fish is a high-protein low-fat food with a range of health benefits. White-fleshed fish, especially oilier fish is believed to contain substantial quantities of omega-3s or the so called “good” fats. Furthermore, fish does not contain the “bad” fats commonly found in red meat. As such, nutritional supplements made from fish oil are growing more popular. Sales of such supplements in the United States alone have more than tripled since 1998, reaching US$190 million in 2003. Omega-3 fatty acids in fish play an important role in reducing the risk of heart disease. The two fatty acids found in oily fish, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have been recognized by The American Heart Association (AHA) as vital to sustain the heart. More recent studies also suggest that high levels of omega-3 fats do help reduce symptoms of mental health and developmental disease, ranging from dyslexia to bipolar disorder. Despite the health benefits provided by fish, several research studies have shown that fish or fish oil supplements can contain unsafe level of environmental pollutants such as dioxins, PCBs (polychlorinated biphenyls), and heavy metals such as mercury. Take salmons for instance. Farmed salmon, most commonly eaten, contains significantly higher levels of dioxins and toxins such as PCBs than wild salmon. PCBs are chemical cocktails used as coolants and lubricants in transformers. They can cause developmental disorders and other health problems for young children. PCBs have been banned in the United States since 1979, but they still persist in the environment and end up in animal fat. When farmed salmon from United States grocery stores was tested, it was found to contain 16 times the PCBs found in wild salmon, 4 times the levels in beef, and 3.4 times the levels found in other seafood. Similar studies established that farm-raised salmon contains between 3 and 10 times more dioxins than wild salmon. Mercury contamination has been another major concern. It can harm the nervous system, especially to developing foetus and the very young. However, it is possible to minimize exposure to toxins by eating fish that are known to have lower levels of contaminants. Also, avoid fried fish as frying seals in chemical pollutants whereas grilling, broiling or poaching allows fat to drain away. Fat is where the pollutants are usually stored. Another advice is not to eat the same kind of fish more than once a week. The United States group, Environmental Defense, lists the best and worst seafood choices: Best – Atlantic wide salmon; Atlantic sea herring; US farmed abalone; US farmed catfish; Atlantic mackerel; Alaskan halibut, sardines, oysters; Alaskan black cod; New Zealand mussels; Alaskan halibut.