Magnesium and health outcomes: an umbrella review of systematic reviews and meta-analyses of observational and intervention studies

Purpose To map and grade all health outcomes associated with magnesium (Mg) intake and supplementation using an umbrella review. Methods Umbrella review of systematic reviews with meta-analyses of observational studies and randomized controlled trials (RCTs) using placebo/no intervention as control group. We assessed meta-analyses of observational studies based on random-effect summary effect sizes and their p values, 95% prediction intervals, heterogeneity, small-study effects and excess significance. For meta-analyses of RCTs, outcomes with a random-effect p value