A cross-sectional study on the effect of dietary zinc intake on the relationship between serum vitamin D3 and HOMA-IR

Introduction: Serum vitamin D-3 concentration is associated with the risk of insulin resistance. Zinc has also been reported to be associated with a lower risk of insulin resistance. In addition, zinc is an essential cofactor in the activation of vitamin D-3. However, the effect of dietary zinc intake on the relationship between vitamin D-3 and insulin resistance risk has not been fully studied. Therefore, we designed this cross-sectional study to assess the impact of changes in zinc intake on the relationship between vitamin D-3 and insulin resistance risk. Study design and methods: This study analyzed data from the national Health and Nutrition Examination Survey (NHANES) from 2005 to 2018, involving 9,545 participants. Participants were stratified by zinc intake category (low zinc intake<9.58 mg/day; High zinc intake: >= 9.58 mg/day). Results: In this cross-sectional study, serum vitamin D-3 levels were independently associated with the risk of insulin resistance in both the low and high Zinc intakes (beta: -0.26, 95%Cl: -0.56 similar to 0.04 vs. beta: -0.56, 95%Cl: -1.01 similar to-0.11). In addition, this association was influenced by different dietary zinc intakes (interaction P<0.05). Conclusions: Our results suggest that zinc intake may influence the association between serum vitamin D-3 and the risk of insulin resistance. Further randomized controlled trials are needed to provide more evidence of this finding.