How It Works
Cofactor for ATP (all ATP exists as Mg-ATP complex). NMDA receptor antagonist (calming). Required for vitamin D activation. Regulates muscle contraction/relaxation (Ca2+ antagonist). GABA receptor modulation.
Dosage & Timing
Optimal Timing
Evening preferred — promotes relaxation and sleep. Take with food to reduce GI effects. Avoid within 2 hours of calcium supplements (competition for absorption).
Blood Markers to Monitor
- RBC Magnesium (more accurate than serum)
- Serum Magnesium (acute changes only)
Deficiency Symptoms
- Muscle cramps/twitching
- Poor sleep
- Anxiety/irritability
- Fatigue
- Heart palpitations
- Headaches
- Constipation
Cycling & Duration
No cycling required — safe for continuous daily use.
Best Forms (Ranked)
Best absorption. Minimal GI effects. Good for sleep/anxiety. Our top pick.
Good absorption. Laxative effect at high doses. Cheaper than glycinate.
Best brain penetration. Improves cognitive function. Expensive.
Poor absorption (~4%). Mostly laxative. Avoid for supplementation.
Good for fibromyalgia/muscle pain. Energizing — take morning/afternoon.
Evidence-Based Benefits
- Improved sleep quality and latency
- Reduced muscle cramps and twitching
- Testosterone support (particularly if deficient)
- Blood pressure reduction (5-10 mmHg systolic)
- Migraine prevention (600mg/d)
- Insulin sensitivity improvement
Side Effects & Safety
- GI distress/diarrhea (especially citrate, oxide)
- Sedation at high doses
- Renal impairment patients: caution
✅ Good For
- Essentially everyone (50%+ of population deficient)
- Athletes (increased loss through sweat)
- Poor sleepers
- Muscle cramp sufferers
- High stress individuals
⚠️ Skip If
- Severe renal impairment
- Myasthenia gravis (may worsen symptoms)
Stacks Well With
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