BALTIMORE, MARYLAND. The daily consumption of fish oils (omega-3 polyunsaturated fatty acids) can significantly lower blood pressure in people suffering from hypertension. The benefit of the fish oils is comparable to that obtainable by sodium reduction and weight loss. A group of medical researchers at the Johns Hopkins Medical School evaluated the results of 17 clinical trials involving supplementation with fish oils for periods of three months or less.
They found that the consumption of 3 grams per day of fish oil (6-10 capsules) or more led to impressive reductions in the blood pressure of hypertensive individuals. Systolic pressure was lowered by an average of 5.5 mm Hg and diastolic pressure was lowered by 3.5 mm Hg. The effect was found to be more pronounced at higher blood pressures and no significant effects were noted in people with normal blood pressure. Twenty-eight percent of the participants in the trials reported side effects such as a fishy taste or belching. The doctors suggest that fish oil supplementation may be a valuable therapy in patients with borderline hypertension who would otherwise be candidates for conventional drug therapy. They point out that the effects of long term (> 3 months) supplementation are unknown and that lower dosages than 3 g/day may be desirable and perhaps as effective.
Appel, Lawrence J., et al. Does supplementation of diet with "fish oil" reduce blood pressure? Archives of Internal Medicine, Vol. 153, June 28, 1993, pp. 1429-38