When it comes to magnesium supplementation, the form you choose matters. Magnesium glycinate and magnesium citrate are two of the most popular options—but which one is right for you? Let's examine the science behind each form.
Why Magnesium Matters
Magnesium is involved in over 300 enzymatic reactions in the body:
- Muscle and nerve function
- Protein synthesis
- Blood glucose control
- Blood pressure regulation
- Energy production
Yet many people are deficient—estimates suggest up to 50% of the population doesn't get enough from diet alone.
Absorption: The Science
Both forms are considered highly bioavailable. Research shows that organic magnesium salts (like citrate and glycinate) have higher bioavailability than inorganic forms like oxide [1].
Magnesium Citrate
- Bound to: Citric acid
- Absorption: Well-absorbed in the digestive tract
- Common uses: General magnesium supplementation
- Note: Often used as a gentle laxative at higher doses
Magnesium Glycinate
- Bound to: Glycine (an amino acid)
- Absorption: May have superior bioavailability due to chelation [2]
- Common uses: Sleep, relaxation, sensitive stomachs
- Note: Most gentle on the digestive system
Which Should You Choose?
Choose Magnesium Citrate If:
- You want general magnesium supplementation
- You occasionally experience constipation
- You're on a budget (typically less expensive)
- You don't have digestive sensitivities
Choose Magnesium Glycinate If:
- You have a sensitive stomach
- You're taking it primarily for sleep and relaxation
- You want the most bioavailable form
- You're taking higher doses
- You experience loose stools with other forms
The Research Verdict
According to recent research, the absorption differences between forms are modest and potentially clinically insignificant for many people [3]. However, gastrointestinal tolerance often determines which form is appropriate for each individual.
Key insight: The best magnesium supplement is one you'll actually take consistently.
Comparing the Two
| Factor | Citrate | Glycinate |
|---|---|---|
| Absorption | Good | Excellent |
| Bioavailability | High | Higher |
| GI Tolerance | Moderate | Excellent |
| Sleep Benefits | Good | Best |
| Cost | Lower | Higher |
| Laxative Effect | Yes | Minimal |
Practical Recommendations
For General Health
Both forms work well. If budget is a concern, citrate provides excellent value.
For Sleep and Relaxation
Glycinate is generally preferred due to:
- The glycine component has calming effects
- Better absorption means more magnesium reaches cells
- Gentler on the stomach allows for evening dosing
For Athletes
Both work, but glycinate may offer slight advantages for recovery due to better absorption and potential sleep benefits.
Dosage Guidelines
- General: 200-400mg elemental magnesium daily
- With food: Reduces stomach upset
- Evening: Best for sleep benefits
- Cycling: Not necessary—magnesium can be taken continuously
Quality Considerations
Look for:
- Third-party testing (NSF, USP)
- Elemental magnesium listed
- Minimal fillers
- Reputable manufacturers
The Bottom Line
While absorption differences exist, both citrate and glycinate are excellent choices. Glycinate edges ahead for those with sensitive stomachs or those prioritizing sleep, while citrate offers great value for general supplementation.
As always, consult with a healthcare provider if you have kidney disease or take medications that affect magnesium levels.
References
[1] PMC. Predicting and Testing Bioavailability of Magnesium Supplements.
[2] BodyBio. Magnesium Glycinate vs Citrate research.
[3] Verywell Health 2025. Magnesium Glycinate vs Citrate.