Supplementation with flaxseed oil versus sunflowerseed oil in healthy young men consuming a low fat diet: Effects on platelet composition and function.
Supplementation with flaxseed oil versus sunflowerseed oil in healthy young men consuming a low fat diet: Effects on platelet composition and function.
Year: 1995
Authors: M A Allman, M M Pena, D Pang.
Publication Name: Europ. J. Clin. Nutr.
Publication Details: Volume 49; Number 3; Page 169.
Abstract:
Nutritional research has established the antithrombotic properties of the long-chain n-3 PUFA, in particular EPA and DHA, found in the oils of fatty fish. Diets rich in the long chain n-3 PUFAs inhibit platelet aggregation via decreased production of TXA2. However, the average Western style diet is low in fish and many consumers are not able to incorporate the dietary levels of EPA and DHA necessary to obtain the beneficial effects of n-3 PUFAs. ALA, the precursor for EPA and DHA, is found in high concentrations in flaxseed and flaxseed oil, both of which are sold as EFA supplements throughout North American. The objective of the present study was to compare the effects of supplementing a low fat diet (about 30% of total energy) supplemented with high ALA from flaxseed or with high LA from sunflower oil on platelet composition and function. Eleven healthy young males participated in the study and were randomly allocated to one of the two oils for 23 days. Subjects consumed their traditional diet in which fat was restricted for 14 days followed by the experimental period in which 40 g of either flaxseed (n=5) or sunflower oil (n=6) was added. The flaxseed diet was comprised of 34% fat, 10.5% SFA, 6% MUFA, 13% PUFA. The n-6:n-3 ratio of this diet was 1:2 and contained 5% n-6 FA and 9% n-3 FA. The sunflower oil diet was comprised of 40% fat, 16% SFA, 9% MUFA, 12% PUFA. The n-6:n-3 ratio of this diet was 31:1 and contained 12% n-6 FA and 0.4% n-3 FA. Following the flaxseed diet, high in ALA, platelet EPA more than doubled indicating the strong conversion of ALA into the long chain n-3 PUFA. Platelet ALA levels were also elevated. In comparison, platelet ALA and EPA remained unchanged in the sunflower oil group. As a result, the platelet EPA:AA ratio, considered a marker for TXB production and platelet aggregation potential, significantly increased in the flaxseed group from 0.02 to 0.05. This ratio remained unaltered in the sunflower oil fed group. The aggregation response induced by 0.75 and 2 ug of collagen was significantly decreased in subjects fed the flaxseed. The authors concluded that their study provides further evidence that consumption of flaxseed oil, rich in ALA, may offer protective effects against cardiovascular disease and thrombosis. Oils rich in ALA clearly have dietary advantages in comparison to LA rich oils due to their ability to decrease the tendency of platelets to aggregate. The author suggest that further research is required to establish the optimal ratio of ALA:LA in the diet.
