Bone mineral density is associated with composite dietary antioxidant index among US adults: results from NHANES

This cross-sectional study investigated the relationship between composite dietary antioxidant index (CDAI) and individual dietary antioxidant intakes, including vitamins A, C, and E, zinc, selenium, and carotenoids, and bone mineral density (BMD) in the US population aged 20 years older. We found a positive correlation between CDAI and femoral BMD. Moreover, higher intakes of vitamin C, vitamin E, selenium, zinc, and carotenoids were associated with higher femoral BMD. Introduction While individual dietary antioxidants have shown beneficial effects on bone metabolism, the diverse and potentially interacting nature of dietary components may limit the accuracy of evaluating their impact on bone health. Thus, this study aims to investigate the association between CDAI and BMD. Additionally, we explore the relationship between the intake of individual components of the CDAI and BMD. Methods The CDAI is a novel index evaluating total dietary antioxidant intake, considering vitamins A, C, and E, zinc, selenium, and carotenoids. A cross-sectional analysis was conducted using data from participants aged & GE; 20 in the National Health and Nutrition Examination Survey (2005-2010, 2013-2014, and 2017-2018). We utilized multivariate linear regression models to examine the relationship between CDAI, individual dietary antioxidants, including vitamins A, C, and E, zinc, selenium, carotenoids, and femoral BMD. Results The final analysis included 10,584 participants with a mean age of 50.73 & PLUSMN; 16.65 years. After multivariate adjustment, the second to fourth quartiles of CDAI (- 2.00-0.04, 0.04-2.54, and 2.54-70.78) exhibited higher femoral BMD compared to the first quartile of CADI (- 7.34 to - 2.00). Multiple regression analysis revealed that higher intakes of vitamin C, vitamin E, selenium, zinc, and carotenoids were associated with higher femoral BMD. Conclusions CDAI serves as a comprehensive tool for evaluating the overall antioxidant capacity of antioxidants in diets. Additionally, our study shows a positive correlation between CDAI and BMD, which indicates that the combined intake of dietary antioxidants may help reduce the risk of osteoporosis in adults.