Inverse association between dietary antioxidant indices and dietary inflammatory potential in jordanian adults: a cross-sectional study

BACKGROUND: The Dietary Antioxidant Index (DAI) and Dietary Inflammatory Index (DII) measure the antioxidant capacity and inflammatory potential of diets, respectively, and are inversely associated with the risk of chronic disease. AIMS: This study examines DAI characteristics and their association with DII in Jordanian adults, adjusting for sex, body mass index (BMI), and waist circumference (WC). METHODS: A cross-sectional study was conducted, and 391 adults were randomly included. Sociodemographic, lifestyle, and anthropometric data (BMI and WC) were collected using standardized protocols. Dietary intake was assessed using a validated 157-item FFQ, from which DAI, Dietary Antioxidant Quality Score (DAQS), and DII were calculated using established international methods. RESULTS: Females, individuals with overweight/obesity, and those with central obesity had significantly higher DAI and DAQS scores (p < 0.001). Unexpectedly, participants with overweight/obesity and central obesity were more frequently represented in higher antioxidant score categories, whereas normal-weight and normal-WC individuals clustered in lower antioxidant score categories (p < 0.001). DAI and DAQS decreased progressively across increasing DII quartiles (p < 0.001), showing a moderate, significant inverse correlation with DII (r ≈ - 0.32 to - 0.37). Regression analysis confirmed that higher antioxidant indices were associated with lower DII scores, accounting for 14-16% of the variance after adjustment. CONCLUSION: Dietary antioxidant indices were inversely and gradually associated with DII, independent of sex and adiposity measures. These findings indicate substantial overlap between antioxidant-rich dietary patterns and lower inflammatory dietary profiles.