Association Between Diet-Derived Antioxidants and Asthma: Insights from The NHANES Survey 2003-2018 and Mendelian Randomization Analysis

Abstract

BackgroundMany studies have reported correlations between diet-derived antioxidants and asthma. Nevertheless, the probable association between diet-derived antioxidants and asthma remains a matter of discussion. ObjectivesWe explored the association between Diet-Derived Antioxidants and Asthma. MethodsWe used data from the 2003-2018 National Health and Nutrition Examination Survey (NHANES) to assess the relationship between diet-derived antioxidants and asthma and a two-sample Mendelian randomization (MR) study was employed to assess the causal associations between lifelong diet-derived circulating antioxidant levels and the risk of asthma. ResultsParticipants with asthma were more likely to be young-to-middle-aged females, smokers, have lower income, belong to non-Hispanic Black ethnicity, have a high school education, have a BMI over 30. The dietary intakes of vitamin C, zinc, selenium, and CDAI were negatively associated with asthma risk (Vitamin C: OR=0.76, 95% CI: 0.63-0.91, P=0.032; Zinc: OR=0.86, 95% CI: 0.75 - 1.00, P=0.046; Selenium: OR=0.85, 95% CI: 0.73-0.98, P=0.004; CDAI: OR=0.80, 95% CI: 0.65-0.97, P=0.027). There was a significant nonlinear relationship between the dietary intake of vitamin C, zinc, and selenium and the risk of asthma (Pnon-linear < 0.05). However, no causal link between circulating antioxidants and asthma risk was found in the MR analysis. Sensitivity analyses supported the robustness of the results. ConclusionIn the observational study, we identified a negative correlation between the dietary intake of vitamin C, zinc, selenium, and CDAI and asthma risk, while our MR analyses did not find evidence to support a causal relationship between diet-derived antioxidants and the risk of asthma.