The association of psoriasis with composite dietary antioxidant index and its components: a cross-sectional study from the National Health and Nutrition Examination Survey.

Background: Psoriasis is a chronic inflammatory skin disorder associated with various comorbidities. The role of nutrition and dietary antioxidants in psoriasis management has gained attention. The Composite Dietary Antioxidant Index (CDAI) quantifies overall dietary antioxidant intake, but its association with psoriasis remains unclear. This study aimed to investigate the association between the CDAI and psoriasis, as well as the relationship between individual components of CDAI and psoriasis risk.

Methods: Data from the US National Health and Nutrition Examination Survey (NHANES) were analyzed. Baseline characteristics, CDAI scores, and psoriasis status were assessed. Multivariable logistic regression and restricted cubic splines were employed to analyze the association.

Results: The study included 23,311 participants, with 621 diagnosed with psoriasis. Higher CDAI scores were associated with a lower odds ratio (OR) of psoriasis occurrence (OR = 0.72, 95% CI 0.56-0.92, P = 0.009 in Model 3). Vitamin E intake exhibited an inverse correlation with psoriasis risk (OR = 0.76, 95% CI 0.60-0.96, P = 0.039 in Model 3). Other CDAI components did not show significant associations with psoriasis.

Conclusion: This study demonstrates a significant inverse association between CDAI and psoriasis, indicating that higher dietary antioxidant intake is associated with a reduced risk of psoriasis. Specifically, higher vitamin E intake was associated with a lower likelihood of psoriasis. These findings underscore the potential role of dietary antioxidants in psoriasis management. Further research is warranted to elucidate the underlying mechanisms and explore targeted dietary interventions.