The Two Options
Head-to-Head Comparison
| Glycinate | Citrate | |
|---|---|---|
| Bioavailability | High (~80%) | High (~25-35%) |
| Primary use | Sleep, anxiety, muscle | Constipation, repletion |
| Laxative effect | Minimal | Mild to moderate |
| Cost | Higher ($$) | Lower ($) |
| Best taken | Evening (with food) | Morning or before bed |
| Daily dose | 200-400 mg elemental | 200-400 mg elemental |
When to Choose Each
Choose Glycinate when:
- Your goal is sleep quality, anxiety reduction, or muscle relaxation
- You want to avoid laxative effects
- You need a higher daily dose without GI upset
- You're managing chronic stress or HPA-axis issues
Choose Citrate when:
- You have occasional or chronic constipation
- You want general magnesium repletion at low cost
- You can tolerate (or want) mild osmotic effects
- Cost matters and the laxative effect isn't a problem
Verdict
Frequently Asked Questions
Which is better for sleep — glycinate or citrate?
Glycinate is better for sleep. The glycine portion has its own mild calming effect on the nervous system, and glycinate doesn't cause the bowel-stimulating effect that can wake you up at night. Take 200-400 mg of elemental magnesium glycinate 30-60 minutes before bed.
Which one helps constipation?
Citrate, by a wide margin. Magnesium citrate has osmotic laxative effects — it draws water into the bowel, softening stool. Glycinate is fully absorbed before reaching the colon and doesn't produce this effect. For constipation, 200-400 mg magnesium citrate is a reasonable starting dose.
Can I take both forms?
Yes, and many people do. Glycinate at night for sleep, citrate during the day for digestion. Just track your total elemental magnesium intake — staying under 400-500 mg/day total is sensible for most adults.
Does the form really matter?
Yes. The form determines bioavailability and side effect profile. Magnesium oxide (a third common form) has the lowest absorption (~4%) and the strongest laxative effect — fine for constipation, poor for repletion. Glycinate and citrate are both well-absorbed and serve different purposes.