Abstract
BACKGROUND: Circadian Syndrome (CircS) expands on metabolic syndrome (MetS) by including circadian rhythm disturbances and depression. It has been shown to be a better predictor of cardiovascular disease (CVD) than MetS. While magnesium has been linked to circadian rhythm disturbances, its association with CircS remains unclear. This study aimed to investigate the association between dietary magnesium intake and CircS using data from the National Health and Nutrition Examination Survey (NHANES). METHODS: Data from 10,486 adults aged 20 years and above who attended the 2005-2016 NHANES were analyzed in this cross-sectional study. Magnesium intake was assessed using two 24-h dietary recalls. CircS was defined based on components of MetS plus short sleep and depression, with a cut-off of ≥ 4 components. Multivariable logistic regression was used to assess the association between magnesium intake and CircS. RESULTS: The mean participant age was 50.3 (SD 17.6) years. The prevalence of CircS was 41.3%, decreasing from 47.3% in the lowest quartile of magnesium intake to 35.2% in the highest. After adjusting for age, gender, ethnicity, energy intake, education, and lifestyle factors, higher magnesium intake was linked to lower CircS prevalence. The adjusted odds ratios (ORs) (95% CI) across magnesium intake quartiles were: 1.00, 0.80 (0.68-0.95), 0.75 (0.64-0.87), and 0.61 (0.49-0.76) (p for trend < 0.001). The association remained significant after additional adjustment for healthy eating index. No significant interaction was found between magnesium intake and race, gender, smoking, alcohol use, or physical activity. CONCLUSIONS: Higher magnesium intake was associated with lower CircS prevalence in U.S. adults, suggesting a potential role for magnesium in circadian health.