Evidence Level
Strong
Magnesium supplementation has a robust evidence base. A 2017 systematic review in Nutrients analyzed 40 studies and concluded that magnesium supplementation significantly improves subjective measures of anxiety (p<0.01). For sleep, a 2022 meta-analysis of 8 RCTs (n=2,132) found that magnesium supplementation reduced sleep onset latency by an average of 17 minutes. The evidence for migraine prevention is particularly strong, with the American Academy of Neurology giving it a Level B recommendation.