Magnesium

Tier 1 — strong evidence · Sleep · Cognition · Metabolic

Second most deficient mineral in Western diets — nearly 50% of adults fall below the estimated average requirement. Involved in over 300 enzymatic reactions, ATP synthesis, DNA repair, nerve transmission, and muscle relaxation. A 2024 meta-analysis (Behers, PMID 39519450) confirmed magnesium supplementation at doses up to 360 mg/day reduces systolic blood pressure by 3.03 mmHg in normotensive adults, with larger effects at durations over 3 months. A 2021 systematic review (Mah, PMID 33865376, 3 RCTs) found oral magnesium reduced sleep onset latency by 17 minutes in older adults, though…

Dose: 200–400 mg/day elemental magnesium from glycinate, malate, or citrate. The supplement UL is 350 mg/day from non-food sources for adults (diarrhea risk above this). Divide doses if taking >200 mg/day.