The association between dietary mineral intake and bone mineral density: a cross-sectional study.

Objectives: Minerals are essential for maintaining bone health; however, the relationship between specific mineral intakes and bone mineral density (BMD) remains insufficiently understood. This study aims to examine the associations between the intakes of dietary minerals, including calcium (Ca), phosphorus (P), magnesium (Mg), iron (Fe), zinc (Zn), copper (Cu), sodium (Na), potassium (K), and selenium (Se), and BMD.

Methods: A cross-sectional study was conducted using data from the National Health and Nutrition Examination Survey (NHANES). Multivariate weighted generalized linear regression and smooth curve fitting were applied to evaluate the associations between dietary mineral intakes and BMD. Furthermore, subgroup analyses and interaction tests were performed to assess the consistency of these associations across different individual characteristics.

Results: A total of 11,520 representative adult participants were included in the study. Tertile-based categorical analysis revealed significant positive correlations between the intakes of Ca [β: 0.0096, 95% Confidence Interval (95% CI): (0.0001, 0.0192)], Mg [β: 0.0207, 95% CI: (0.0107, 0.0307)], Fe [β: 0.0157, 95% CI: (0.0061, 0.0253)], Zn [β: 0.0106, 95% CI: (0.0020, 0.0192)], Cu [β: 0.0088, 95% CI: (0.0000, 0.0176)], Na [β: 0.0126, 95% CI: (0.0024, 0.0228)], and Se [β: 0.0123, 95% CI: (0.0024, 0.0221)] and BMD (all P < 0.05). Smooth curve fitting and threshold effect analyses further demonstrated nonlinear relationships between mineral intakes and BMD. Subgroup analyses identified significant modulating effects of sex on the associations with Ca, Fe, and Na, as well as an interaction between diabetic status and Ca intake (all P for interaction < 0.05).

Conclusion: This study elucidates the intricate relationships between dietary mineral intakes and BMD. These findings offer preliminary insights into the potential for tailored nutritional strategies in bone health management across diverse populations.