Association between Dietary Antioxidants and Atherosclerotic Cardiovascular Disease in South Korea: Insights from a Comprehensive Cross-Sectional Analysis

<b>Background/Objectives</b>: The multifactorial nature of atherosclerotic cardiovascular disease (ASCVD) implicates genetic, environmental, and dietary habits. Antioxidants found in foods have garnered attention for their potential role in mitigating ASCVD risk by combating oxidative stress. This study seeks to confirm the findings of previous research through a large-scale cross-sectional analysis performed in a unique population with Korea National Health and Nutrition Examination Survey data to explore the association between the composite dietary antioxidant index (CDAI) and ASCVD prevalence among middle- and old-aged individuals in South Korea. <b>Methods</b>: This study includes data from 2016 to 2021. The CDAI was calculated based on nutrition intake, including zinc, beta-carotene, vitamin A, vitamin C, vitamin E, and docosahexaenoic acid. This cross-sectional analysis explored the relationship between the CDAI and ASCVD after adjusting for relevant covariates. Logistic regression models were employed, and subgroup analyses by sex were conducted to discern sex-specific effects. <b>Results</b>: A total of 19,818 individuals were analyzed, with 7.0% of them diagnosed with ASCVD. CDAI distribution and antioxidant analyses revealed higher CDAI levels in non-ASCVD individuals. Standardized antioxidant values increased across CDAI quartiles. Initially, a significant association (odds ratio [95% confidence interval]: 0.96 [0.94-0.99]) was found between the CDAI and ASCVD, which was attenuated after adjusting for covariates (1.0 [0.98-1.02]). Subgroup analyses by sex showed nuanced associations, with the CDAI potentially reducing the risk of ASCVD in men (0.71 [0.53-0.94]) while increasing it in women (1.4 [1.01-1.95]). <b>Conclusions</b>: This study provides valuable insights into the association between dietary antioxidant intake and the risk of ASCVD, highlighting sex-specific differences.