Relationship between composite dietary antioxidant index and depression among overweight and obese adults

The use of specific dietary patterns to alleviate depressive symptoms has gained increasing recognition. The Composite Dietary Antioxidant Index (CDAI) is a crucial criterion for assessing antioxidant diets. We examined the relationship between CDAI and depression among overweight and obese adults through a cross-sectional study conducted in the United States.

We used weighted multivariate logistic regression models with subgroup analysis to study the relationship between CDAI and depression. Generalized additive models were used to determine whether there was a nonlinear association between them. We developed a two-piece linear regression model to calculate the inflection point utilizing a recursive strategy.

After adjusting for confounding variables, the odds ratios (ORs; 95 % CI) for the correlation between CDAI and depression were 0.75 (0.67, 0.84). A saturation effect emerged for the overweight group, following which we calculated the inflection point for the overweight population, which displayed ORs (95 % CI) of 0.62 (0.47, 0.80) before the inflection point of 0.83 and the ORs (95 % CI) of 1.01 (0.77, 1.31) after 0.83. The interaction was statistically significant in the sex stratification of the obese population.

Our study highlighted a negative association between CDAI and depression among overweight and obese adults. Saturation effects and sex differences were observed in the overweight population.