Associations of blood trace elements with bone mineral density: a population-based study in US adults

Background This study aimed to investigate the association between blood trace elements and bone mineral density (BMD) and to determine the association between blood trace elements and the risk of low BMD/osteoporosis among US adults. Methods We performed a cross-sectional study using data from National Health and Nutrition Examination Survey (NHANES, 2011-2016). Multivariable linear regression models were employed to assess the associations of BMD in lumbar spine (LS-BMD), pelvic (PV-BMD) and total femur (TF-BMD) with blood trace elements, including Fe, Zn, Cu, Se, Mn, Cd, Pb, Hg. Additionally, the associations of low BMD/osteoporosis with blood trace elements were also evaluated using multivariable logistic regression. Results Higher blood Pb levels were found associated with decreased LS-BMD (p for trend < 0.001), PV-BMD (p for trend = 0.007), and TF-BMD (p for trend = 0.003) in female, while higher blood Se levels were associated with increased PV-BMD in female (p for trend = 0.042); no linear association between BMD and other blood trace element was observed. Also, significant associations were found between Pb levels and the prevalence of low BMD (p for trend = 0.030) and the prevalence of osteoporosis (p for trend = 0.036), while association between other blood trace elements and low BMD/osteoporosis was not observed. Conclusion This study provides comprehensive insight into the association between blood trace elements and BMD and supports a detrimental effect of blood Pb levels on bone mass in women. Considering our analysis from a representative US general population, further study is warranted for the extreme levels of blood trace elements on bone metabolism.