Dietary magnesium intake as modifier of the association between vitamin D deficiency and risk of anemia in the US children aged 2–14 years: A cross-sectional study

Vitamin D deficiency and magnesium deficiency are both associated with an increased risk of anemia. However, the impact of dietary magnesium intake on the relationship between vitamin D deficiency and anemia risk has yet to be determined. In this study, 11,471 children aged 2 to 14 years were enrolled using data from the National Health and Nutrition Examination Survey 2005 to 2018. The participants were divided into low and high magnesium intake groups based on a quantile cutoff of < 208.5 and ≥ 208.5 mg/d, respectively. Participants who were vitamin D deficiency had an increased risk of anemia (odds ratio = 1.492, 95% confidence intervals: 1.072-2.077). The incidence of anemia differed in low-dietary magnesium intake and high-dietary magnesium intake groups (odds ratio, 95% confidence interval: 1.992, 1.264-3.139 vs 0.934, 0.564-1.548, respectively), indicating an interaction between vitamin D deficiency and dietary magnesium intake in anemia risk (P = .009), which suggests that a magnesium-rich diet may reduce the risk of vitamin D deficiency-induced anemia. the findings highlight the synergistic effect of low-dietary magnesium intake and vitamin D deficiency on the increased risk of anemia in children.