Magnesium Citrate vs Magnesium Glycinate: Which Is Better?
Last updated: August 2026 · Reviewed by the FactoWiki Editorial Team for clarity and source accuracy
Glycinate if you want magnesium without a laxative effect — for sleep, cramps, anxiety or general repletion. Citrate if constipation is also something you want to address. Both are well absorbed, which is the main thing that separates them from magnesium oxide.
Key takeaways
- Citrate has a real laxative effect; glycinate largely does not.
- Both absorb far better than magnesium oxide, which is the form to avoid for repletion.
- Check the elemental magnesium figure — citrate is ~16% by weight, glycinate ~14%.
What actually separates them
Both are organic magnesium salts and both absorb well. The difference is what happens to the fraction that is not absorbed. Citrate draws water into the intestine osmotically, which produces the laxative effect — useful if you are constipated, unwelcome if you are not. Glycinate is chelated to glycine and absorbed through amino acid transport routes, leaving much less unabsorbed magnesium in the gut.
The glycine bonus
Glycinate supplies glycine as well as magnesium, and glycine has its own modest sleep evidence — 3 g before bed improved subjective sleep quality in Japanese trials. The amount of glycine in a magnesium glycinate dose is well below that, so do not over-read it, but it is a reason glycinate is the usual evening recommendation.
Read the elemental figure
This trips people up constantly. A 500 mg magnesium citrate capsule supplies roughly 80 mg of actual magnesium. Labels show either the compound weight or the elemental weight and rarely make clear which. Aim for 200–400 mg elemental daily, and note the supplemental upper limit is 350 mg.
Key ingredients to understand
The ingredients most relevant to this question, with what the evidence actually supports:
- Magnesium Citrate — Magnesium citrate is well absorbed and has a notable laxative effect, which makes it a good choice if constipation is part of the picture and a…
- Magnesium Glycinate — Magnesium glycinate (magnesium bound to glycine) is a gentle, well-absorbed form popular for sleep and relaxation, and easier on the stomach…
- Magnesium — Magnesium is an essential mineral involved in hundreds of body processes, including nerve and muscle function, energy and blood-sugar control.…
- Glycine — Glycine is the smallest amino acid and a building block the body uses for collagen and many other roles. As a supplement it is taken mainly as a…
Frequently asked questions
Can I take both?
Yes. Some people take glycinate in the evening and citrate when they need the bowel effect. Just add the elemental magnesium together.
What about magnesium oxide?
Poorly absorbed at roughly 4% and mainly useful as a laxative or antacid. It is common in cheap multivitamins because it is inexpensive and lets a label show a big number.
How long before magnesium helps?
2–4 weeks for most effects. Bowel effects from citrate are immediate.
Related on FactoWiki
- All health answers
- Ingredient evidence guides
- Magnesium Citrate — ingredient guide
- Magnesium Glycinate — ingredient guide
- How we review
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