Associations of Copper Intake with Bone Mineral Density and Osteoporosis in Adults: Data from the National Health and Nutrition Examination Survey.

Some studies have suggested an association between serum copper and bone density. Few studies have explored the association between copper intake and osteoporosis and bone mineral density (BMD). Our research aims to assess the associations of copper intake with the risk of osteoporosis in United States adults using the National Health and Nutritional Examination Surveys (NHANES). A total of 8224 individuals were included in our study. Osteoporosis was defined that BMD values surpass 2.5 standard deviations (SD) below the mean of the young adult reference group. Copper intake from diets and supplements was estimated by using two 24-h recall surveys. After adjustment for all the covariates of interest, the odds ratios (ORs) (95% confidence interval (CI)) between the risk of osteoporosis and total copper intake across quartiles 3 and 4 compared with quartile 1 were 0.48 (0.31-0.74) (P < 0.01) and 0.41 (0.26-0.65) (P < 0.01), respectively. The mean total femur BMD and total spine BMD of the highest dietary copper intake quartile (Cu 1.51 mg/d) was 0.03 g/cm and 0.02 g/cm greater than the lowest quartile. Our results indicate that dietary and total copper intake was positively associated with increasing BMD in US adults and negatively associated with the risk of osteoporosis in US adults.