What is difference between magnesium glycinate and magnesium bisglycinate?

Why one compound has two names

The chelate is one magnesium atom held by two glycine molecules. Chemists count the ligands, so bisglycinate; everyday labelling drops the counter, so glycinate; both point at the identical structure and many bottles, the worked example included, use one name on the front and the other in the ingredients. There is no stronger version, no purer version and no version to seek out by name, and any listing implying bisglycinate is an upgrade on glycinate is marketing a synonym. The phrase magnesium as magnesium glycinate, another variant this query carries, is the panel's way of saying the elemental figure comes from the glycinate compound, which is bookkeeping, not a third product.

What actually varies between glycinate products

Three things, none of them the name. The percentage: fully reacted chelate is about 14% magnesium, while buffered bisglycinate, blended to raise the density, reaches 20%, and an honest label prints the figure, as the worked example does. The elemental dose per serving, which the percentage and the compound weight produce between them, running from 40mg tokens to the full 300mg. And the additions, from nothing at all to sleep-formula herbs. Two bottles both saying glycinate can therefore differ fivefold in magnesium, which is why the comparison to run is never glycinate versus bisglycinate but elemental line versus elemental line.

How the two names behave across UK listings

Search either spelling on Amazon UK and the results overlap almost completely, because sellers stuff both words into titles precisely so that they do. Around the two names orbit a small vocabulary worth decoding once: chelated magnesium means the same glycinate family stated generically; buffered bisglycinate means the 20% material, chelate blended with a little oxide to raise density, legitimate when the elemental line is printed; fully reacted means the 14% material with no blending; and trademarked ingredient names signal a branded raw material, fine but not a different molecule. None of these words changes what you are buying; the percentage and the elemental line do. A listing leaning hard on the vocabulary while hiding those two numbers has told you which game it is playing.

The habit that ends the confusion, and the worked example

Ignore the front-of-pack vocabulary entirely and read two lines: the ingredients, where the form and its percentage live, and the nutrition panel, where the elemental dose and %NRV live. A product passing on both lines is good under either spelling; a product failing them is poor under either spelling. Futuro Labs Magnesium Glycinate demonstrates the whole page on one label: Magnesium Glycinate on the front, magnesium bisglycinate 20% in the ingredients, elemental magnesium 300mg at 80% NRV on the panel, 2 vegan capsules a serving, UK made under GMP and BRC, panels shown, £19.99 for 180 capsules, 22p a day. The difference between magnesium glycinate and magnesium bisglycinate is a spelling choice; the differences that cost you money live two lines lower down.

What to check on the label

Questions people also ask

Is magnesium bisglycinate better than magnesium glycinate?

No; they are the same compound. Differences between products come from the percentage, the elemental dose and any additions.

What does bis mean in bisglycinate?

Two: the chelate holds two glycine molecules per magnesium atom. The everyday name simply drops the counter.

What is the difference between magnesium 500mg and magnesium glycinate?

Usually an oxide tablet's elemental claim against a chelate. Oxide's 500mg is about 4% absorbed; compare the glycinate's elemental line against it, not its compound weight.

What does magnesium as magnesium glycinate mean on a panel?

That the elemental figure on that line is supplied by the glycinate compound. It is sourcing information, not a different ingredient.

Which should I search for when buying, glycinate or bisglycinate?

Either; results overlap heavily. Filter by the elemental line, the percentage and a shown panel rather than the spelling.

Sources

1. Futuro Labs Magnesium Glycinate listing, Amazon UK, label and price checked 31 August 2026. https://www.amazon.co.uk/dp/B0BT7Z5VQW
2. Retained Regulation (EU) No 1169/2011, Annex XIII: nutrient reference value for magnesium 375mg. https://www.legislation.gov.uk/eur/2011/1169/annex/XIII
3. Firoz M, Graber M. Bioavailability of US commercial magnesium preparations. Magnesium Research 2001;14(4):257-262. PubMed record
4. The Food Supplements (England) Regulations 2003 (food supplements are regulated as foods in the UK). https://www.legislation.gov.uk/uksi/2003/1387/contents/made
5. EFSA Panel on Dietetic Products, Nutrition and Allergies. Scientific Opinion on the substantiation of health claims related to magnesium. EFSA Journal 2010;8(10):1807. https://efsa.onlinelibrary.wiley.com/doi/10.2903/j.efsa.2010.1807

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