California researchers are embarking on a five-year study to test whether Eskimos have fewer heart attacks because of their high fish oil diet.
"Fish oil may offer great promise in reducing cardiac risk and may even have benefits unrelated to heart disease. But the bottom line is that no one really knows for sure," said Dr. D. Craig Miller, associate professor of cardiovascular surgery at Stanford University Medical Center.
A 1977 study of Greenland Eskimos traced the population's low incidence of heart disease to its high consumption of fish oil. The suggestive evidence was buttressed when later studies found that, when some of the same Eskimos moved to Denmark and changed their diets, their cardiac risk went up.
The central ingredient that appears to keep cardiac risk low is eicosapentaenoic acid, or EPA, the primary ingredient in food supplements such as OMEGA-3. The supplements can be sold without extensive testing or government approval since they are food derivatives, not drugs.
Such capsules contain an amount of concentrated fish oil that only could be duplicated by eating a large amount of cold-water fish.