Association between dietary patterns and depression: an umbrella review of meta-analyses of observational studies and intervention trials

Context: Depression is the most common cause of disease burden worldwide. Objective: An umbrella review has been performed to assess the strength and validity of the available observational and trial evidence for the association be- tween a variety of dietary patterns and depression. Data Sources: MEDLINE/ PubMed, Scopus, Web of Science, EMBASE, PsycINFO, and Cochrane Database were searched. Data Extraction: The Joanna Briggs Institute Umbrella Review Methodology was used. Data Analysis: The review included 19 articles, covering a relatively wide range of dietary patterns: healthy dietary patterns, Mediterranean diet (MedDiet), Dietary Inflammatory Index (DII), Western diet, Dietary Approaches to Stop Hypertension (DASH), vegetarian diets, and other dietary interventions. The methodological quality of the included meta-analyses was generally low or critically low. The strength of the evidence was generally weak, although convincing or suggestive evidence was found for an inverse relationship between MedDiet/DII and depression. Higher adherence to the MedDiet and lower DII score were significantly associated with lower risk of depression. Conclusion: Considering the generally high heterogeneity and low quality of the available evidence, further studies adopting more coherent and uniform methodologies are needed.