Association between serum vitamin C and depression in adults: A cross-sectional study of NHANES from 2017 to 2018

Abstract

Background The objective of this cross-sectional study was to explore the association between serum vitamin C and depression in adults. Methods Data from the 2017–2018 National Health and Nutrition Examination Survey (NHANES) cycle were utilized. Multivariable logistic regressions were applied to assess the association between serum vitamin C and depression. Restricted cubic spline (RCS) regression was conducted to explore the dose-response relationship between serum vitamin C and depression. In addition, we performed stratified and sensitivity analyses to evaluate the stability of the results. Results A total of 4517 participants were included in this study. Among of them, 410 (9.08%) participants suffered depression. In fully adjusted models, serum vitamin C, as a continuous variable, was negatively associated with depression (OR = 0.69, 95%CI: 0.54–0.88, P = 0.003). Similar results were observed when serum vitamin C was analyzed as a categorical variable. The ORs (95% CI) for Q2, Q3, and Q4, with Q1 as the reference, were 1.00 (0.76–1.33), 0.73 (0.54–0.99), and 0.59 (0.42–0.81), respectively. The RCS analysis found a linear negative relationship between serum vitamin C and depression (P for non-linearity = 0.579). Additionally, the inverse associations between serum vitamin C and depression remained robust in stratified and sensitivity analyses. Conclusion Our findings suggested that there was a linear negative relationship between serum vitamin C and the risk of depression, indicating that maintaining sufficient serum vitamin C are recommended due to its potential benefits for protecting against depression.