Relation of homocysteine, folate, and vitamin B12 to bone mineral density of postmenopausal women.

Genetic hyperhomocysteinemia is associated with skeletal abnormalities and osteoporosis. We tested whether levels of homocysteine and critical co-enzymes of homocysteine metabolism, such as vitamin B12 and folate, are related to lumbar spine bone mineral density (BMD) measured by DEXA in 161 postmenopausal women. Folate but not homocysteine or vitamin B12, was lower in osteoporotic than normal women (7.2 +/- 0.9 ng/L vs 11.4 +/- 0.7 ng/L, P < 0.003). Folate, but not homocysteine or vitamin B12, was independently related to BMD (r = 0.254, P < 0.011). BMD progressively increased from the lowest to the highest folate quartile (1.025 +/- 0.03 g/cm2 vs 1.15 +/- 0.03 g/cm2, P < 0.01) even when covaried for weight, which was the only other variable related to BMD. The present data suggest a major association between folate and bone mineralization.