Dr. Ron’s Research Review – August 29, 2012

This week’s research review focuses on EPA for men, DHA for women.

A blinded placebo controlled trial involving 15 male and 15 female subjects. Platelet aggregation was measured at 0, 2, 5 and 24 h post-supplementation with a single dose of either a placebo or EPA or DHA rich oil capsules. EPA was significantly the most effective in reducing platelet aggregation in males at 2, 5 and 24 h post-supplementation (-11%, -10.6%, -20.5% respectively) whereas DHA was not effective relative to placebo. In contrast, in females, DHA significantly reduced platelet aggregation at 24 h (-13.7%) while EPA was not effective. An inverse relationship between testosterone levels and platelet aggregation following EPA supplementation was observed. (Phang, Sinclair et al. 2012)

A placebo-controlled trial was conducted in healthy males and females (n=30). platelet microparticle (MP) activity, platelet microparticle levels and platelet aggregation were measured at 0 and 24 h post-supplementation with either a placebo or EPA- or DHA-rich oil. Both EPA and DHA effectively reduced platelet aggregation at 24 h post-supplementation relative to placebo (-13.3%, P=.006 and -11.9%, P=.016, respectively), but only EPA reduced MP activity (-19.4%, P=.003). When grouped by gender, males showed a similar reduction in both platelet aggregation and MP activity (-20.5%, P=.008; -22%, P=.008) following EPA, while females showed significantly reduced platelet aggregation (-13.7%, P=.04) but not MP activity after DHA only. (Phang, Lincz et al. 2012)

Dr. Ron


Articles

Acute supplementation with eicosapentaenoic acid reduces platelet microparticle activity in healthy subjects

            (Phang, Lincz et al. 2012) Download

BACKGROUND: Dietary supplementation with omega-3 fatty acids has been associated with reduced incidence in thrombotic events. In addition, administration of n-3 polyunsaturated fatty acids (PUFAs) has been shown to rectify elevated platelet microparticle (MP) number and procoagulant activity in post myocardial infarction patients. However, it is unknown whether supplementation can alter these parameters in healthy individuals and if such effects are immediate or require long-term supplementation. We have previously demonstrated a gender-specific effect of LCn-3PUFA supplementation on platelet aggregation in healthy human subjects. Here we extend these findings to include the acute effects of supplementation with EPA- or DHA-rich oils on circulating MP levels and activity in healthy subjects. DESIGN: A placebo-controlled trial was conducted in healthy males and females (n=30). MP activity, MP levels and platelet aggregation were measured at 0 and 24 h postsupplementation with either a placebo or EPA- or DHA-rich oil. RESULTS: Both EPA and DHA effectively reduced platelet aggregation at 24 h postsupplementation relative to placebo (-13.3%, P=.006 and -11.9%, P=.016, respectively), but only EPA reduced MP activity (-19.4%, P=.003). When grouped by gender, males showed a similar reduction in both platelet aggregation and MP activity (-20.5%, P=.008; -22%, P=.008) following EPA, while females showed significantly reduced platelet aggregation (-13.7%, P=.04) but not MP activity after DHA only. CONCLUSION: EPA and DHA exert gender-dependent effects on platelet aggregation and platelet MP activity, but not on MP levels. With respect to thrombotic disease risk, males may benefit more from EPA supplementation.


Gender-specific inhibition of platelet aggregation following omega-3 fatty acid supplementation

            (Phang, Sinclair et al. 2012) Download

BACKGROUND AND AIMS: Increased platelet aggregation is a major risk factor for heart attacks, stroke and thrombosis. Long chain omega-3 polyunsaturated fatty acids (LCn-3PUFA; eicosapentaenoic acid, EPA; docosahexaenoic acid, DHA) reduce platelet aggregation; however studies in the published literature involving EPA and/or DHA supplementation have yielded equivocal results. Recent in vitro studies have demonstrated that inhibition of platelet aggregation by LCn-3PUFA is gender specific. We examined the acute effects of dietary supplementation with EPA or DHA rich oils on platelet aggregation in healthy male and females. METHODS AND RESULTS: A blinded placebo controlled trial involving 15 male and 15 female subjects. Platelet aggregation was measured at 0, 2, 5 and 24 h post-supplementation with a single dose of either a placebo or EPA or DHA rich oil capsules. The relationship between LCn-3PUFA and platelet activity at each time point was examined according to gender vs. treatment. EPA was significantly the most effective in reducing platelet aggregation in males at 2, 5 and 24 h post-supplementation (-11%, -10.6%, -20.5% respectively) whereas DHA was not effective relative to placebo. In contrast, in females, DHA significantly reduced platelet aggregation at 24 h (-13.7%) while EPA was not effective. An inverse relationship between testosterone levels and platelet aggregation following EPA supplementation was observed. CONCLUSION: Interactions between sex hormones and omega-3 fatty acids exist to differentially reduce platelet aggregation. For healthy individuals, males may benefit more from EPA supplementation while females are more responsive to DHA.

References

Phang, M., L. Lincz, et al. (2012). "Acute supplementation with eicosapentaenoic acid reduces platelet microparticle activity in healthy subjects." J Nutr Biochem 23(9): 1128-33.

Phang, M., A. J. Sinclair, et al. (2012). "Gender-specific inhibition of platelet aggregation following omega-3 fatty acid supplementation." Nutr Metab Cardiovasc Dis 22(2): 109-14.