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 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.
Results: 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.
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.