Which magnesium form is best?
Magnesium glycinate is best for most people (sleep, anxiety, general). Threonate for brain health. Citrate for digestion. Avoid oxide - only 4% is absorbed.
- Glycinate: best all-around (80% absorbed)
- Threonate: brain-specific
- Oxide: avoid (4% absorbed)
The Bioavailability Problem
Magnesium oxide has about 4% bioavailability - meaning 96% passes straight through you. Magnesium glycinate has around 80% bioavailability. That's a 20x difference.
Quick Tips
- →Oxide is cheap but barely absorbed
- →Glycinate is premium but worth it
Magnesium Glycinate (Best for Sleep & Anxiety)
The glycine amino acid has its own calming effects, making this a double-whammy for relaxation. It's gentle on the stomach and highly absorbed.
Best for: Sleep, anxiety, general deficiency
Dose: 200-400mg before bed
Quick Tips
- →Take 1-2 hours before sleep
- →Won't cause digestive issues
Magnesium Threonate (Best for Brain)
The only form shown to cross the blood-brain barrier effectively. Studies show improvements in memory and cognitive function.
Best for: Memory, focus, cognitive support
Dose: 144mg elemental (usually 2000mg threonate)
Quick Tips
- →Most expensive but unique for brain
- →Split dose: AM and PM
Magnesium Citrate (Best for Digestion)
Good absorption and promotes healthy bowel movements.
Best for: Constipation, general deficiency
Dose: 200-400mg
Quick Tips
- →Start low to avoid loose stools
- →Good all-around form
Forms to Avoid
Magnesium Oxide: 4% absorption. Basically a laxative.
Magnesium Sulfate: External use only (Epsom salts).
Magnesium Carbonate: Poor absorption.
Quick Tips
- →Check labels - oxide is in most cheap multivitamins
- →Quality over price
Key Takeaways
For most people, magnesium glycinate is the best all-around choice. If brain health is your focus, threonate is worth the premium. Avoid oxide unless you need a laxative.
Ingredients Mentioned
Magnesium Glycinate
Magnesium L-Threonate
Magnesium Citrate
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