Effect of folic acid on bone metabolism: a randomized double blind clinical trial in postmenopausal osteoporotic women

Background: In spite of several studies, the impact of homocysteine level and folic acid supplementation on bone metabolism is yet to be recognized. In this registered clinical trial (IRCT2014042217385N1), we aimed to find out the power of 6-month folic acid supplementation on homocysteine level and bone metabolism. Methods: Forty postmenopausal osteoporotic women (50 to 87 years) were enrolled in the study. All participants were randomized to receive folic acid 1 mg (n = 17) or placebo (n = 14). At baseline, 3 months, and finally 6 months post intervention, the level of homocysteine, vitamin B12, and bone biomarkers were measured. Results: Both groups were similar at baseline. The homocysteine decreased in both groups but statistically non-significant (P 0.05). The changes of the serum level of vitamin B12, osteocalcin, and β cross laps were significant between groups after 6 months (P ≤ 0.05). Conclusion: The trend of changes of bone biomarkers after 6 months folic acid supplementation shows that homocysteine concentration and/or folic acid supplementation have impact on the rate of bone metabolism. However, further investigations by larger sample size and differentiating age and gender are still needed to clarify the exact role of folate, homocysteine and vitamin B12.