Magnesium: Complete Guide
Essential mineral involved in 300+ enzymatic reactions. 70% of adults are deficient.
Quick Summary
Essential mineral involved in 300+ enzymatic reactions. 70% of adults are deficient. 200-400mg elemental magnesium daily. Best form: Glycinate.
What is Magnesium?
Magnesium is the fourth most abundant mineral in your body and participates in over 300 enzymatic reactions including energy production, protein synthesis, muscle and nerve function, blood sugar control, and blood pressure regulation. Despite its importance, 50-70% of Americans don't get enough from diet alone.
Who Should Consider Magnesium?
- People with poor sleep (magnesium deficiency is linked to insomnia)
- Those experiencing anxiety or stress (depletes magnesium rapidly)
- Athletes and active individuals (lost through sweat)
- People on proton pump inhibitors (reduce magnesium absorption)
- Those with muscle cramps, restless legs, or twitches
- Anyone over 50 (absorption decreases with age)
How It Works
Magnesium activates ATP (your cellular energy currency), regulates calcium and potassium transport across cell membranes, and modulates the NMDA receptor (important for sleep and anxiety). It also serves as a cofactor for vitamin D activation. Without adequate magnesium, vitamin D can't do its job.
Forms Comparison
Different forms of Magnesium have varying absorption rates and best uses. Here's how they compare:
| Form | Bioavailability | Best For |
|---|---|---|
| Glycinate | 80% | Sleep, anxiety, muscle relaxation. Highly absorbable and gentle. |
| Citrate | 25% | General use, constipation relief. Good all-around choice. |
| L-Threonate | 60% | Brain health, memory. Crosses blood-brain barrier uniquely. |
| Malate | 35% | Energy, fibromyalgia. Supports ATP production. |
| Taurate | 40% | Heart health, blood pressure. Cardioprotective. |
| Oxide | 4% | Avoid. Poorly absorbed, mostly laxative effect. |
Our recommendation: Glycinate for most people due to superior absorption and tolerability.
Benefits & Evidence
Magnesium has 3 strongly-evidenced benefits and 3 moderately-evidenced benefits.
Sleep quality improvement
strong evidence12 RCTs show 17% improvement in sleep quality scores
Anxiety reduction
strong evidenceMeta-analysis: 18 studies, significant GAD-7 improvement
Muscle cramp prevention
strong evidence60% reduction in nocturnal leg cramps
Blood pressure regulation
moderate evidenceAverage 5-7 mmHg systolic reduction
Migraine frequency reduction
moderate evidence400-600mg reduced migraine days by 42%
Blood sugar support
moderate evidenceImproves insulin sensitivity in deficient individuals
Dosing & Timing
Recommended Doses
Timing
Side Effects & Interactions
Possible Side Effects
- Loose stools/diarrhea. Common at high doses
- Nausea. Occasional
- Drowsiness. Common with glycinate
Interactions to Know
- May reduce absorption of antibiotics (take 2-4 hours apart)
- Can enhance blood pressure medication effects
- May affect thyroid medication absorption
- Synergistic with vitamin D (enhances D activation)
Frequently Asked Questions
For sleep benefits, take 30-60 minutes before bed. For general health, morning or evening works. Consistency matters more than timing.
Related Topics
About this information: Our analysis of Magnesium is based on peer-reviewed research from PubMed, ClinicalTrials.gov, and NIH databases. These statements have not been evaluated by the FDA. Supplements are not intended to diagnose, treat, cure, or prevent any disease.
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