Association between circulating antioxidant concentrations and bone mineral density in an adult population

Evidence regarding the relationship between various circulating antioxidants and bone mineral density (BMD) remains controversial. This study aimed to evaluate the associations between circulating antioxidant levels and BMD in a adult population. We included 398 participants from the midlife in the United States (MIDUS) study who underwent BMD measurements of lumbar spine (L1–L4) and total femur, as well as circulating antioxidant concentrations . The relationships between blood antioxidants (total lutein, zeaxanthin, alpha-carotene, 13-cis-beta-carotene, all trans-beta-carotene, gamma-tocopherol, alpha-tocopherol, total lycopene, beta-cryptoxanthin and retinol) and BMD value in lumbar spine and femur were examined. Univariate correlation analysis revealed positive associations between four blood antioxidants (total lutein, 13-cis-beta-carotene, alpha-carotene and all trans-beta-carotene) and BMD value at both sites (lumbar spine and femur)After adjusting for demographic characteristics and lifestyle factors, sensitivity analyses demonstrated significant associations of total lutein (P for linear trend = 0.038), 13-cis-beta-carotene (P for linear trend = 0.044), and alpha-carotene (P for linear trend = 0.019) with lumbar spine BMD. For femoral BMD, 13-cis-beta-carotene (P for linear trend = 0.010) and alpha-carotene (P for linear trend = 0.007) remained significantly associated. Trend tests suggested that these associations weakened as antioxidant levels increased. Higher circulating levels of total lutein, 13-cis-beta-carotene, and alpha-carotene were strongly associated with increased BMD in the lumbar spine and femur. Further prospective studies are warranted to confirm these findings.