Dose-response association between the intake of various subtypes of polyunsaturated fatty acids and depression

Background: Depression is a major global mental health issue. Previous studies have suggested an association between the intake of polyunsaturated fatty acids (PUFAs) and depression, but the conclusions remain controversial. Additionally, there is limited research on the relationship between the intake of specific fatty acid subtypes, such as linoleic acid (LA), arachidonic acid (AA), alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and Docosapentaenoic acid (DPA), and depression. Objective: The relationship between different types of PUFAs and depression risks remains unclear. This study aimed to investigate how the intake of various subtypes of n-3 and n-6 PUFAs correlates with depression. Methods: Participants from the National Health and Nutrition Examination Survey (NHANES) database, spanning from 2005 to 2018, were categorized into two groups: those with depression and those without, based on Patient Health Questionnaire-9 scores. The average daily intake of each PUFAs subtype was assessed through two 24-h dietary recall interviews, propensity score matching was employed to address baseline disparities, and multivariate logistic regression analysis to identify independent markers. Results: The study included 18,798 participants, of whom 1287 were classified as having depression. Postpropensity score matching, multivariate logistic regression analysis revealed an inverse correlation between the intake of AA, ALA, EPA, and DHA and the risk of depression. Restricted cubic spline analysis demonstrated a linear inverse relationship between AA, ALA and EPA intake and depression. Conversely, DHA intake exhibited a nonlinear relationship with depression. No significant association was found between LA or DPA intake and depression risk. Conclusion: Different types of PUFAs appear to influence depression risks differently in adults, with increased intake, AA, ALA, EPA and DHA providing a protective effect against depression.