Do dietary antioxidants prevent postmenopausal bone loss?

The role of dietary antioxidants in osteoporosis has not been well explored. The objective of this study was to examine the relationship between the dietary antioxidants, vitamin E and beta-carotene, and hip bone mineral density (BMD) in postmenopausal women. Subjects were 1892 screenees, aged 55- 80 years, who were volunteers for a clinical trial. Bone densitometry and osteoporosis risk factor information was obtained during screening. Dietary and supplement information was obtained by mailed food frequency and vitamin supplement questionnaires. We found no evidence of an association between dietary and/or supplemental vitamin E and bone density of the femoral neck. Dietary beta-carotene, adjusted for age and weight was positively associated with hip BMD (β=1.5x10^-6 gm/cm², p-0.05). Further adjustment for osteoporosis risk factors diminished the association (β=0.7x10^-6 gm/cm², p=0.38). Neither total nor supplemental beta-carotene intake was found to be associated with BMD. We did not find that vitamin E or beta-carotene was associated with femoral neck bone density in postmenopausal women, however, the potential role of antioxidants and other nutrients in postmenopausal bone loss warrants further study, including research of other bone sites.