American Journal of Clinical Nutrition, Vol 53, 1165-1170, Copyright © 1991 by The American Society for Clinical Nutrition, Inc

ORIGINAL RESEARCH COMMUNICATIONS

Comparison of the absorption and effect on platelet function of a single dose of n-3 fatty acids given as fish or fish oil

DI Silverman, JA Ware, FM Sacks and RC Pasternak
Charles A Dana Research Institute, Cardiovascular Division, Beth Israel Hospital, Boston, MA 02215.

To compare their relative absorption and effect on platelet function, concentrated fish oil and tuna were given to 10 subjects in a randomized crossover study. Although plasma enrichment of eicosapentaenoic acid (EPA) from either preparation was similar, relative absorption of EPA from tuna was significantly greater than that from fish oil (46.6 +/- 3.0 mg.L-1.g EPA-1 from tuna compared with 16 +/- 1.0 mg.L-1.g EPA-1 from fish oil, P less than 0.001). Relative absorption of docosahexaenoic acid (DHA) was equivalent (54.0 +/- 9.0 mg.L-1.g DHA-1 from tuna, 56 +/- 9.0 mg.L-1.g DHA-1 from fish oil, NS). Platelet aggregation in response to the endoperoxide analog U46619 was significantly diminished after either preparation but aggregation in response to other agonists, bleeding time, and membrane n-3 (omega-3) fatty acid content were not changed. Thus, n-3 fatty acids are well absorbed after one dose of either tuna or fish oil but EPA absorption appears to be more efficient from tuna. Additionally, a single dose of n-3 fatty acids decreases platelet aggregation by a mechanism not requiring incorporation into platelet membranes.