Magnesium Glycinate vs Citrate: How to Choose the Right Form
The Short Version
If you're taking magnesium primarily for sleep or relaxation, glycinate is the better pick — its bound glycine amino acid has calming properties and it's gentler on the stomach. If you need a higher elemental magnesium dose per capsule or want mild bowel regularity support, citrate delivers more magnesium per gram and is the more practical choice.
Key Differences
| Factor | Magnesium Glycinate | Magnesium Citrate |
|---|---|---|
| GI Tolerance | Very gentle — rarely causes loose stools even at higher doses | Can cause loose stools or diarrhea at moderate-to-high doses due to osmotic water draw |
| Sleep & Relaxation | Glycine component may independently support sleep quality (Bannai et al., 2012, n=11; Inagawa et al., 2006, n=15) | No additional calming effect beyond correcting deficiency |
| Elemental Magnesium per Gram | ~14% elemental Mg — requires more capsules to hit the same dose | ~16% elemental Mg — slightly more efficient per gram |
| Bioavailability | High — chelated forms show strong absorption in human studies (Schuette et al., JPEN, 1994, n=14) | High — citrate consistently outperforms oxide in absorption studies (Lindberg et al., Magnes Res, 1990, n=46) |
| Bowel Regularity Support | Minimal effect on bowel motility | Mild osmotic laxative — commonly used for occasional constipation |
| Price per Serving | Typically $0.15–$0.30 per serving — slightly more expensive | Typically $0.08–$0.20 per serving — generally cheaper |
Best For
Sleep support and evening relaxation
glycine's calming properties complement magnesium's muscle-relaxing effects
Sensitive stomachs
well-tolerated even at higher doses without GI side effects
Anxiety and stress management
commonly recommended by practitioners for its calming profile
General magnesium repletion on a budget
more elemental Mg per gram at a lower price
Occasional constipation relief
mild osmotic effect supports bowel regularity
People who tolerate it well and want a straightforward, well-studied form
People who tolerate it well and want a straightforward, well-studied form
Evidence Snapshot
Both forms have solid absorption data. Citrate's bioavailability advantage over oxide is well-established (Lindberg et al., Magnes Res, 1990, n=46; Walker et al., Magnes Res, 2003, n=46). Glycinate's absorption has been demonstrated in metabolic studies, though head-to-head comparisons with citrate specifically are limited (Schuette et al., JPEN, 1994, n=14). The sleep angle for glycinate rests partly on glycine research rather than glycinate-specific trials. Bannai et al. (2012, n=11) and Inagawa et al. (2006, n=15) showed subjective sleep improvements with 3g glycine. A larger RCT on magnesium supplementation broadly (Abbasi et al., J Res Med Sci, 2012, n=46) found that 500mg magnesium improved sleep quality scores in elderly participants, though the form used was not glycinate. The evidence is suggestive but not definitive for glycinate as a sleep-specific form.
Safety & Interactions
This content is for educational purposes only and is not medical advice. These statements have not been evaluated by the FDA. Always consult your healthcare provider before starting any supplement.