Dietary fiber intake moderates the impact of blood cadmium on depression: a nationally representative cross-sectional study

Abstract

Background Cadmium (Cd) is a very poisonous pollutant in the environment that has harmful implications on the neurological system. While high fiber intake is beneficial for mental health, it remains unknown whether the recommended basis for dietary fiber intake (DFI) (14 g/1000 kcal per day) can alleviate Cd-induced depression. Methods The investigation employed data from the National Health and Nutrition Examination Survey (NHANES) conducted between the years 2005 and 2020. The research encompassed individuals who had information on blood Cd concentrations, two 24-hour dietary recalls, and depression diagnosis. We deployed weighted logistic regression analyses to estimate the association of exposure to Cd and DFI with depression risk. Results The adjusted ORs (95% CI) for depression were 1.33 (95% CI: 1.08, 1.65) and 1.64 (95% CI: 1.38, 1.94) for the third and fourth quartiles of blood Cd concentrations, respectively ( P trend < 0.001). Doubling DFI was connected with a 0.78-fold (95% CI: 0.71, 0.85) decrease in the risk of depression. Participants below recommended DFI levels had a greater depression risk with higher blood Cd concentrations: OR of 1.39 (95% CI: 1.11, 1.73) for the third and 1.67 (95% CI: 1.40, 1.98) for the fourth quartile. No significant association between Cd exposure and depression was perceived for participants meeting recommended DFI levels. Conclusions Higher blood Cd burden was associated with elevated depression risk, while recommended DFI could alleviate this effect. High-fiber dietary pattern may counteract the deleterious effect of environmental pollutants such as Cd on depression. Clinical trial number Not applicable. Supplementary Information The online version contains supplementary material available at 10.1186/s12889-024-21146-9.