Association Between Magnesium Intake and Chronic Kidney Diseases and Kidney Stones in Adults Aged 50 years and Older: Dose-Response Analysis of a Nationally Representative Population-Based Study.
Level 4 - case-series / case-control
Cross-sectional analysis of survey data (NHANES 2007-2018)
PubMed 39547432 · doi:10.1053/j.jrn.2024.11.004
What was done
Researchers analyzed data from adults aged 50 years and older participating in the 2007–2018 National Health and Nutrition Examination Survey (NHANES). Magnesium intake from diet and supplements was assessed via structured dietary recalls. Chronic kidney disease (CKD) was defined as estimated glomerular filtration rate <60 mL/min/1.73 m², and kidney stone history was identified by questionnaire. Dose-response patterns and sex-stratified associations were modeled using restricted cubic splines.
What was found
The weighted prevalence was 12.16% for CKD and 13.13% for kidney stones. Nonlinear inverse relationships were observed between magnesium intake and both CKD (P for nonlinearity < .01) and kidney stones (P for nonlinearity = .02). Odds dropped sharply with increasing intake before plateauing or weakening beyond 350 mg/day (odds ratio [95% CI] for CKD: 0.60 [0.46–0.78]; for kidney stones: 0.77 [0.61–0.98]). The inverse association with CKD appeared in both sexes, whereas the inverse association with kidney stones was statistically significant only in females.
Why it matters
This analysis identifies an intake threshold of approximately 350 mg/day of magnesium associated with lower odds of CKD and kidney stones in older adults, providing a quantitative reference for future prospective studies.
Limits
The cross-sectional design prevents causal inference or determination of temporality. Total participant count (n) is not reported in the abstract. Magnesium intake relied on self-reported dietary recalls prone to measurement error, and kidney stone status was self-reported without clinical verification.
Cited by
- supports Adequate magnesium intake, such as magnesium citrate and magnesium glycinate, helps prevent kidney stones.