Vitamin D, Calcium, Magnesium, and Potassium Consumption and Markers of Glucose Metabolism in the Hispanic Community Health Study/Study of Latinos

OBJECTIVE This was a cross-sectional study associating vitamin D, calcium, magnesium, and potassium intakes with markers of glucose metabolism in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL). METHODS HCHS/SOL is a multicenter, prospective, population-based cohort study on Hispanics/Latinos aged 18-74 years in the US. For this analysis, we included 10,609 participants who were free of diabetes. Analysis of covariance was used to assess associations of a range of micronutrient intake on the Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), Hemoglobin A1c (HbA1c), and 2-hour post-oral glucose tolerance test (2h-plasma glucose) separately for normoglycemic and with pre-diabetes, after controlling for important confounders. All analyses accounted for the complex sample design and sampling weights. RESULTS HOMA-IR levels were significantly lower among adults with intakes in the highest quartile for vitamin D, magnesium, and potassium compared to the respective lowest quartiles, for those with normoglycemia and pre-diabetes, even after adjusting for confounders, such as diet quality (p < 0.05). For those with pre-diabetes, HOMA-IR levels were also significantly lower for those in the highest quartile of calcium intake. However, 2h-plasma glucose was significantly higher in those with intakes higher than quartile 1 for vitamin D and calcium among those with normoglycemia and significantly higher in quartile 3 of potassium intake for those with pre-diabetes, p < 0.05. No significant associations were found for HbA1c in either group. CONCLUSIONS Higher consumption of vitamin D, magnesium, and potassium are associated with optimal levels of HOMA-IR among participants with normoglycemia and pre-diabetes.