Low-dose folic acid supplementation reduces plasma levels of the cardiovascular risk factor homocysteine in postmenopausal women.

Abstract

The aim of our randomized, controlled trial was to verify the effect of folic acid supplementation on homocysteine levels in postmenopausal women. Thirty-six women were divided randomly into 2 groups as follows: a placebo group (n = 18) and a group receiving 500 microg folic acid per day for 4 weeks (n = 18). To assess concentrations of plasma homocysteine, venous blood samples were taken on enrollment and after 4 weeks of treatment. Mean plasma homocysteine levels were 10.9 +/- 2.7 micromol/L in the placebo group and 7.8 +/- 2.35 micromol/L (P <.01) in the group receiving 500 microg folic acid per day for 4 weeks. The thirds (referred to as tertiles) of women with the highest baseline homocysteine plasma levels showed the greatest reduction in homocysteine, with a mean decrease of 4.35 micromol/L (32%; P <.01), in comparison with a decrease of 3.35 micromol/L (29%; P <.01) in the middle tertile and 1.3 micromol/L (22.4%; P =.09) in the lower tertile. The results show that low doses of folic acid are associated with a significant reduction in plasma concentrations of homocysteine. The highest initial levels of homocysteine showed the most important reduction after therapy.