Dietary Magnesium Intake in Relation to Depression in Adults: A GRADE-Assessed Systematic Review and Dose–Response Meta-analysis of Epidemiologic Studies

Abstract Context The relation of magnesium (Mg) intake with depression was previously investigated by meta-analyses. However, due to limited data, a dose–response analysis was not performed. Objective Considering the recently published articles, a systematic review and dose–response meta-analysis was conducted to summarize the relation of dietary Mg intake with depression in adults. Data Sources Medline (PubMed), ISI Web of Science, Scopus, and Google Scholar were comprehensively searched up to August 2023. Data Extraction Observational studies that reported the relation of dietary Mg intake and depression in adults were included and their data were extracted. Data Analysis A total of 63 214 participants from 10 cross-sectional and 3 cohort studies were included in the current study. Pooling 15 effect sizes from 12 studies (including 50 275 participants) revealed that individuals with the highest Mg intake had a 34% lower risk of depression, compared with those with the lowest Mg intake (RR: 0.66; 95% CI: 0.57, 0.78). Moreover, the linear dose–response analysis revealed that each 100-mg/d increment in Mg intake was associated with a 7% reduced risk of depression (RR: 0.93; 95% CI: 0.90, 0.96). Additionally, based on nonlinear dose–response analysis, increasing Mg intake from 170 to 370 mg/d was associated with a reduced risk of depression. Analyses were also conducted on 9 studies (49 558 participants) with representative populations, and similar results were found in the meta-analysis (RR: 0.71; 95% CI: 0.61, 0.83) and linear (RR: 0.93; 95% CI: 0.90, 0.96) and nonlinear dose–response analysis. Conclusion The current study shows an inverse dose–dependent association between dietary Mg intakes and risk of depression in both a general and representative population of adults in a dose–response manner. Systematic Review Registration PROSPERO registration no. CRD42024506570.