Association Between Dietary Inflammatory and Oxidative Balance Scores and Skin Cancer Risk: The Mediating Role of Accelerated Phenotypic Aging.

BACKGROUND: Skin cancer is known to be associated with aging, oxidative stress, and inflammation. The present study aimed to explore the association between PhenoAge, dietary inflammatory index (DII), and dietary oxidative balance index (DOBS) with skin cancer risk. METHODS: A total of 474 individuals aged over 20 years who had information on DII, DOBS, PhenoAge, socioeconomic and demographic factors, and self-reported skin cancer, and 16,154 without skin cancer were included in the National Health and Nutrition Examination Survey database (2005-2018). The combination of DII/DOBS was categorized into 3 categories: inflammation- and oxidation-promoting diet, inflammation- and oxidation-reducing diet, and composite diet. We applied logistic regression to estimate odds ratios (ORs) for the association of DII/DOBS and PhenoAge with skin cancer risk, after adjusting for covariates and survey year. RESULTS: PhenoAge was associated with an increased likelihood of skin cancer (OR 1.07, 95% CI 1.06 to 1.08, p < 0.001). DII and DOBS were associated with PhenoAge advancement of OR 1.28 (95% CI 1.20 to 1.36), OR 0.95 (95% CI 0.94 to 0.96), respectively (p < 0.001). After adjusting for all covariates, the comparison between the inflammation-oxidation-promoting diet and the inflammation-oxidation-reducing diet had a positive relationship with skin cancer (OR 2.19, 95% CI 1.29 to 3.72, p = 0.004). PhenoAge mediated 28.06% of the associations between DII/DOBS and skin cancer risk (p < 0.05). The association remained in the subgroup analysis. CONCLUSION: Our results suggest that an inflammation- and oxidation-promoting diet is related to increased skin cancer risk and may be partly mediated by PhenoAge.