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

OBJECTIVE: The aim of our randomized, controlled trial was to verify the effect of folic acid supplementation on homocysteine levels in postmenopausal women. STUDY DESIGN: Thirty-six women were divided randomly into 2 groups as follows: a placebo group (n = 18) and a group receiving 500 μg 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. RESULTS: Mean plasma homocysteine levels were 10.9 ± 2.7 μmol/L in the placebo group and 7.8 ± 2.35 μmol/L (P < .01) in the group receiving 500 μg 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 μmol/L (32%; P < .01), in comparison with a decrease of 3.35 μmol/L (29%; P < .01) in the middle tertile and 1.3 μmol/L (22.4%; P = .09) in the lower tertile. CONCLUSIONS: 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.