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Ingredients explained
Magnesium forms explained: glycinate, citrate and oxide
The short answer
The form of magnesium changes how well you absorb it and how kind it is on your stomach, more than it changes what magnesium does in the body. For most people a well-tolerated chelated form like bisglycinate is the sensible pick. Citrate is well absorbed but can loosen the bowels. Oxide is cheap and high in elemental magnesium but less well absorbed. A lot of good products, ours included, combine forms to balance absorption, tolerance and dose.
- The form affects absorption and tolerance, not the underlying job magnesium does.
- Bisglycinate (a glycinate chelate): gentle and well tolerated.
- Citrate: well absorbed, mild laxative effect for some.
- Oxide: cheap, high elemental magnesium, lower absorption.
What does magnesium do?
Magnesium is a mineral your body uses for a long list of ordinary jobs. In the terms the UK allows a supplement to describe, magnesium contributes to normal muscle function, to the normal working of the nervous system, to normal energy-yielding metabolism, to a reduction of tiredness and fatigue, to normal psychological function, and to the maintenance of normal bones. The reference intake in the UK is around 300 mg a day for men and 270 mg for women, and you will get a good share of that from nuts, seeds, wholegrains and leafy greens if you eat enough of them, which many of us do not, week to week.
The forms compared
| Form | Absorption | Tolerance | In short |
|---|---|---|---|
| Bisglycinate (glycinate chelate) | Good | Gentle, well tolerated | A sensible everyday choice |
| Citrate | Good | Can loosen the bowels | Fine, but watch the laxative effect |
| Oxide | Lower | Usually fine, but can be laxative in bulk | Cheap, high elemental magnesium, less absorbed |
| Malate, taurate and others | Varies | Varies | Niche picks, thinner evidence |
The names sound technical, but two things decide it: how much you absorb, and whether it upsets your stomach. Bisglycinate scores well on both, which is why it is the form most people are pointed to first.
Absorption versus tolerance
There is a trade-off hiding in the numbers. Oxide is dense in magnesium by weight, so a small tablet can look impressive on the label, though only a small share is absorbed. Bisglycinate looks weaker on paper but delivers more of what it carries and tends to sit more comfortably. Neither is a miracle form. For something you take every day, being able to take it comfortably is what keeps you taking it.
What our complex uses, and why
Our magnesium is a buffered complex that combines magnesium bisglycinate and magnesium oxide, delivering 200 mg of elemental magnesium, which is 53% of the daily reference intake, plus a small blend of magnesium-rich plants. The reason to combine the two is practical: bisglycinate for tolerance and absorption, a little oxide to keep the dose meaningful in a capsule you can swallow. We do not make claims about sleep or stress on this page, because those are not authorised uses in the UK, and we would rather stick to what the evidence and the rules allow.
FAQ
Questions people ask
Which magnesium is best?
For most people, a gentle, well-absorbed form like bisglycinate. Citrate is a fine alternative if the laxative effect does not bother you.
Is magnesium bisglycinate better than citrate?
It tends to be gentler on the stomach. Citrate is well absorbed too, but is more likely to loosen the bowels.
What is magnesium oxide?
A cheap, high-strength form. You absorb a smaller share of it, which is why it is often blended with a better-absorbed form.
How much magnesium do I need?
The UK reference intake is about 300 mg a day for men and 270 mg for women, from food and supplements combined.
Keep reading
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The NATURELO nutrition team
Reviewed by Milan Shah, Certificate in Plant-Based Nutrition, T. Colin Campbell Center for Nutrition Studies (eCornell).
This guide is general information, not a substitute for advice from your GP, midwife or pharmacist.
