Go to Health – Omega-3 fatty acids
Humans have been eating aquatic animals since the beginning of our evolution. We depended on the rivers, lakes, and marshes to survive in the African heat. Some anthropologists believe we were only able to become large-brained because we regularly included fish and other aquatic animals in our diet. The beneficial fats in fish and shellfish are known as EPA and DHA (also called omega-3 fatty acids); they are made by microalgae in seawater, consumed by fish and accumulated in their fat and organs.. When we eat fish, shellfish or fish oil capsules, we experience some of the following benefits:
*Heart - a current review of 15 large studies, published in the American Journal of Nutrition, states that EPA and DHA consumption markedly reduces the risk of cardiac death. The scientists recommended establishment of a Dietary Reference Intake for EPA and DHA (250-500 mg/day) to reduce the risk of heart disease – the leading cause of death of men and women in the US and other developed countries. The mechanisms by which omega-3 fatty acids work is thought to be by suppressing irregular heart beats, decreasing clotting and inflammation, and lowering triglycerides.
*Brain - the human brain is composed of about 60% fat; studies show that omega-3 fatty acids are essential for nervous tissue growth and function. In 1996, the Journal of the American Medical Association published a study comparing the prevalence of depression across ten nations. The survey showed how the lifetime and annual rates for depression vary widely from country to country. (1.5 in every 100 adults in Taiwan experience depression in their lifetimes while the figure is 19 for every 100 adults in Beirut). A 1998 study published in The Lancet compared this data with fish consumption, finding the higher consuming populations had less depression. A 2003 study published in the American Journal of Psychiatry compared similar cross-national data, involving bipolar disorder, again finding a strong correlation between this illness and seafood consumption. Dr.Andrew Stoll, a Harvard psychiatrist, uses fish oil capsules to treat depression, bipolar disease, and anxiety, in addition to standard treatment in serious cases. His book ‘The Omega-3 Connection’ explains the use of fish oil capsules for mood stabilization in many illnesses, including post-partum depression. Pediatricians are aware that improving maternal DHA/EPA nutrition decreases the risk of poor infant and child visual and neural development. Pregnant and breast feeding mothers are often advised to include (very low mercury) fish or fish oil in their diet, and some infant formulas are now available with added omega-3s.
*Vegetarians – Vegan omega-3 capsules made from microalgae are sold in natural food stores. Walnuts, flax, pumpkin seed and purslane contain a type of fat similar to fish oil, called alpha linolenic acid. This compound is converted to EPA in the body, but the conversion is not complete. Both EPA and DHA are found in fish oil, which makes it the most desirable nutrient for omega-3s. Concern about mercury in fish makes it important to eat wisely, avoiding large fish like swordfish and shark. Look for the words ‘molecularly distilled’ on fish oil caps. Here’s a good website for avoiding both mercury and endangered species of fish:
Sadja Greenwood, MD