Magnesium: The Complete Guide

Magnesium is involved in over 300 enzymatic reactions — yet nearly half of Americans don't get enough from food. Choosing the right form is what separates noticeable results from zero effect. This guide covers every form, every goal, and links to every review we've published.

Key Takeaways

  • Magnesium is involved in 300+ enzymatic reactions — deficiency is widespread and affects sleep, anxiety, muscle function, and energy.
  • Form matters: magnesium oxide has ~4% bioavailability; glycinate and threonate absorb at 40%+.
  • For sleep and anxiety: magnesium glycinate is the top choice — chelated, gentle on digestion, activates GABA receptors.
  • For brain health: magnesium L-threonate is the only form clinically shown to cross the blood-brain barrier.
  • For energy and muscle recovery: magnesium malate supports ATP production and reduces exercise-related fatigue.
  • Clinical dose: 200–400 mg elemental magnesium per day, taken at night for sleep benefit.

Articles in This Guide

9 articles covering every magnesium form, comparison, and use case — ranked roughly by where to start.

Magnesium Supplements: Complete Guide to Every Form, Goal, and Top Pick

Start Here

The master hub article. Covers all forms — glycinate, citrate, malate, threonate — with comparison table, goal matching, and top-rated product picks. Start here.

Best Magnesium Supplement 2026: Top Picks for Performance

Head-to-head comparison of the top magnesium supplements for energy, athletic performance, and general health. Includes G6-scored product rankings.

Best Magnesium for Sleep 2026: Glycinate vs Citrate Compared

Science-backed analysis of which magnesium form works best for sleep onset and sleep quality. Side-by-side glycinate vs citrate breakdown.

Best Magnesium Supplement for Anxiety and Sleep 2026

Focused on anxiety-driven sleep disruption. Reviews HPA axis research and ranks products by their glycinate content, third-party testing, and clinical dose.

Best Magnesium Glycinate Supplement 2026: The Chelated Form Reviewed

Deep dive into chelated magnesium glycinate. Covers bioavailability data, clinical dose, product purity, and what separates good brands from cheap oxide blends.

Best Magnesium Glycinate Supplements for Sleep 2026: Evidence-Based Picks for Deeper Rest

Ranks magnesium glycinate products specifically for sleep quality. Evaluates elemental dose, form purity, and RCT alignment.

Best Magnesium L-Threonate Supplement for Brain Health 2026

The only magnesium form shown to meaningfully raise brain magnesium levels. Reviews Magtein and competitor products with cognitive benefit data.

Magnesium Glycinate vs Malate vs Citrate: Which Form for Your Goal?

Goal-by-goal comparison: anxiety, sleep, energy, digestion, and muscle recovery. Clear recommendations based on mechanism, not marketing.

Magnesium Glycinate vs L-Threonate for Sleep: Which Works?

Head-to-head on sleep specifically. Covers GABA activation (glycinate) vs brain magnesium elevation (threonate) and which matters more for sleep quality.