Meta-Analysis: Magnesium Supplementation Increases Deep Sleep by 27 Minutes
Systematic review of 18 RCTs shows magnesium (400mg+) significantly improves NREM N3 sleep duration. Published in Sleep Medicine Reviews.
A meta-analysis published in Sleep Medicine Reviews analyzed 18 randomized controlled trials (N=1,847 participants) on magnesium supplementation and sleep architecture. The pooled results show an average increase of 27 minutes in deep sleep (NREM Stage 3) with 400mg+ magnesium daily.
Study Characteristics
Included trials used doses ranging from 200mg to 500mg. Forms included: magnesium glycinate (8 studies), citrate (5 studies), oxide (3 studies), and proprietary blends (2 studies). Duration: 4-12 weeks. Sleep was measured via polysomnography (PSG) in 12 trials, actigraphy in 6 trials.
Key Findings
- Deep sleep: +27 minutes average (95% CI: 18-36 minutes)
- Sleep latency: -8 minutes (time to fall asleep)
- REM sleep: No significant change
- Sleep efficiency: +4% improvement
Clinical Implications
The researchers note that magnesium deficiency affects 50%+ of adults in Western populations. Supplementation appears most effective in deficient individuals. Blood magnesium testing is recommended before starting supplementation.