Much attention has been focused recently on the growing popularity of vitamin/mineral-fortified products and vitamin/mineral supplements as a means of promoting health. It seems many people want a "quick fix"--opting to improve their health with these products instead of building a healthy body from a wide variety of food sources.
The latest development for the pill-popping generation is fish oil supplements. The supplements are being lauded because one of their components--omega-3 fatty acid--is implicated in everything from the reduction of serum cholesterol levels in the bloodstream to its ability to relieve the discomforts of immune system diseases, skin disorders and allergies.
But is all this hype about omega-3 just another food fad? The jury is still out on supplementation, but the results of epidemiologic studies on people who eat fish instead of red meat are encouraging.
Physicians and nutritionists gathered in Los Angeles recently for a symposium discussing the possible role of fish oils in the American diet. The discussions included a historical perspective on coronary heart disease in the United States, revealed the results of research data on the effects of fish oils in the body and suggested ways of designing diets to include fish rich in omega-3.
The panel included Dr. William P. Castelli, director of the Framingham Heart Study and lecturer at Harvard University Medical School; Dr. Alexander Leaf, chairman of the department of preventive medicine and clinical epidemiology at Harvard University Medical School; Dr. Artemis P. Simopoulos, director of the Nutritional Sciences International Life Sciences Institute Research Foundation, and Carolyn Crimmins, clinical nutritionist at Massachusetts General Hospital/Harvard Cardiovascular Health Center.
The idea of substituting fish in the diet for more saturated sources of protein like red meat is not new. Neither is supplementation. The American Heart Assn. has stated that it's possible to lower the amount of red meat in the diet by eating more fish and poultry, and mothers have included a dose of cod liver oil in their children's diets for generations. Today's renewed interest in fish oil supplementation comes on the heels of research seeking an explanation for the prevalence of coronary heart disease in Americans. The results were surprising.
Epidemiologic studies of Greenland Eskimos and Japanese and Dutch fishermen confirmed that deaths from cardiovascular disease occurred at a lower rate compared to the death rate for Americans. Yet the Eskimo diet tends to be extremely high in cholesterol; it is largely made up of whale blubber and seal meat, in which fat is excessive. The American diet is also high in fat but the Eskimos also eat large amounts of cold-water fish such as salmon, sardines, mackerel and herring.
The scientists surmised there was something in the blood of fish inhabiting the icy waters of the north that counteracts the Eskimos' high-fat diet. The conclusion was that it was omega-3 fatty acid.
Omega-3 is a polyunsaturated fat that helps to keep the systems of cold-water fish fluid. The Eskimos and Japanese fisherman who ingest fish with high amounts of this substance in their meat tend to benefit from its anti-inflammatory and fluid-inducing effects. "Fish oils counteract the constricting quality of other acids and fats on blood vessels," Leaf said.
The scientists concluded that because of its fluidity, omega-3 is responsible for keeping cholesterol from building up in the arteries of those who eat it, thus reducing the occurrence of diseases like arteriosclerosis, coronary heart disease and high blood pressure, even in high-fat diets.
The clinical definition of omega-3 fatty acid is a technical one that includes terms like eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), triglycerides, lipoproteins and lipids. It is more important to remember that omega-3 fatty acid in fish oil seems to act in three ways to benefit the body: It lowers blood fat levels by sweeping away harmful levels of "bad" fats, which are the major cause of coronary heart disease; it keeps blood flowing by forming platelets (cells that clot) that are less sticky and therefore less likely to clot and jam arteries--a chief cause of strokes; and it lowers total cholesterol levels, which are linked to heart disease.