Magnesium glycinate vs citrate: which to take

Are magnesium glycinate and bisglycinate the same thing?

Yes. Magnesium glycinate, magnesium bisglycinate and magnesium diglycinate are three names for one compound: a magnesium atom bound to two molecules of glycine, an amino acid. "Bis" and "di" both mean two. Glycine makes up most of the weight, so the compound is only about 14% magnesium. In a 2025 trial, each 893 mg capsule of magnesium bisglycinate supplied 125 mg of magnesium.

Read the ingredients list as well as the front of the pack. If a product sold as glycinate also lists magnesium oxide or another magnesium salt, you are buying a blend.

Magnesium glycinate vs citrate: what's the difference?

Citrate has more absorption research behind it than glycinate, but the bigger practical difference is what each one does in your gut.

Magnesium citrate is magnesium bound to citric acid. In a 1990 study, citrate dissolved far better than oxide and raised urinary magnesium, a marker of how much was absorbed, significantly more. A 2003 randomised trial gave 46 healthy adults 300 mg of magnesium a day for 60 days as citrate, an amino-acid chelate or oxide. Citrate and the chelate were both absorbed better than oxide, citrate gave the highest blood levels, and oxide did no better than placebo.

Glycinate has fewer head-to-head studies. A small 1994 trial in 12 people who had had part of the small bowel removed found that overall absorption from magnesium diglycinate and from oxide was about the same, roughly 23% each. In the 2025 trial, where 155 adults took 250 mg of magnesium a day as bisglycinate, nobody in the magnesium group reported stomach problems.

Magnesium citrate is also the osmotic laxative in some UK bowel-cleansing medicines, where it works by holding water in the bowel, which is why higher doses of citrate can loosen stools. If your gut is sensitive, glycinate is a sensible place to start. If citrate suits you, it's a well-studied, well-absorbed choice.

What are the different types of magnesium?

Magnesium supplements are magnesium bound to something else. Reviews sort them into organic salts such as citrate, glycinate and malate, and inorganic ones such as oxide, hydroxide and sulphate, and find that the organic group generally dissolves and absorbs better. The table covers the forms people ask about most. Animal studies don't always match human ones: a 2019 rat study ranked malate highest for absorption and put citrate alongside oxide among the lowest, which doesn't match human trials, where citrate does better than oxide. The table leans on human data where it exists.

What is chelated magnesium?

Chelated magnesium is magnesium held by an organic molecule, usually an amino acid, at more than one point so that the two form a ring. Magnesium glycinate is the usual example: glycine grips the magnesium at two points, and in bisglycinate two glycines bind each magnesium. Chemistry reviews suggest this structure may improve solubility and be gentler on the gut. In the 2003 trial of 46 adults, an amino-acid chelate and citrate were both absorbed better than oxide, and citrate gave the highest blood levels, so the chelate did not come out ahead. Treat "chelated" as a description of how the magnesium is bound. The ingredients list still tells you which compound it is, and the nutrition table tells you how much magnesium you get.

What is magnesium taurate?

Magnesium taurate is magnesium bound to taurine. Most of what has been published on it is animal research or hypothesis papers rather than human trials, so there is little to say about what it does in people. On absorption and safety, EFSA's food additives panel concluded in 2009 that magnesium taurate is readily soluble in water, so its magnesium should be about as available as from other dissociable sources, and that use up to the 250 mg a day upper level for supplemental magnesium was not a safety concern. A 2025 review lists taurate as well absorbed and generally well tolerated, but on the strength of a single reference. Magnesium taurate is different from taurine on its own, which our guide to taurine covers.

What is magnesium malate?

Magnesium malate is magnesium bound to malic acid, which occurs naturally in apples and other fruit. It is an established supplement form: EFSA's 2018 opinion records that an earlier EFSA panel found magnesium malate in food supplements to be of no safety concern in 2006, and that it is on the EU's list of permitted sources for supplements. In a 14-person crossover study described in that opinion, magnesium exposure from di-magnesium malate was higher than from oxide. Little else is known about how well people tolerate it compared with other forms. As with every form sold in the UK, the nutrition table has to show the amount of magnesium itself.

Is magnesium L-threonate available in the UK?

It has been authorised, with conditions. The Food Standards Agency's register lists magnesium L-threonate monohydrate as an authorised novel food in England, Scotland and Wales, with the entry updated on 5 March 2026. It is limited to food supplements giving up to 250 mg of magnesium a day, for adults only: under-18s and pregnant or breastfeeding women are excluded. The Welsh Government's explanatory memorandum adds that a supplement can only use a mineral form that is on an approved list and meets purity criteria, and says its regulations add L-threonate to that list. Only about 7 to 8% of the compound is magnesium, so compare the magnesium figure on the label. The human sleep and memory trials were small and funded by the ingredient's makers.

Which type of magnesium is best?

If you're asking what magnesium is best, the research gives no clear winner: the form matters less than supplement marketing suggests. A 2017 review of magnesium absorption concluded that the type of salt "appears less relevant than is often thought". The dose and how much magnesium you already have matter more, and because the body can't store extra magnesium, absorbing more is usually followed by excreting more. A 2021 systematic review of 14 studies found that organic forms such as citrate tend to be absorbed better than inorganic ones such as oxide, and that any of them can keep levels normal in healthy people. How a product is made counts too. A 2019 study of 15 supplements found that how well a product dissolved predicted absorption better than how much magnesium it contained.

For most people, then, the best magnesium is a well-absorbed form at a dose your gut tolerates, taken regularly. That usually means glycinate or citrate. Skip oxide if absorption is what you want. Threonate delivers only 7 to 8% magnesium by weight, and its human evidence comes mostly from trials funded by its makers. If you're choosing a form for sleep, our guide to magnesium and sleep covers what the trials found.

Is magnesium powder better than capsules?

Not clearly. A magnesium powder is the same compounds as a capsule, ready to stir into water. There is some evidence that dissolving helps. In a 2011 crossover trial in 13 healthy young men, urinary magnesium rose about 40% after effervescent magnesium oxide tablets dissolved in water and about 20% after oxide capsules. Other comparisons, including a chloride solution against slow-release tablets, found no significant difference. So a powder that dissolves fully is a reasonable format, and the form of magnesium inside it and the amount per serving matter at least as much.

What about liquid magnesium and magnesium citrate liquid?

Liquid magnesium is magnesium in a form such as citrate or chloride, already dissolved in water. Magnesium citrate liquid carries the same trade-off as citrate in capsules: it is well absorbed, but it can loosen stools at higher doses. The same compound works as a laxative at much larger doses. One UK bowel-cleansing medicine contains 3.5 g of magnesium oxide and 12 g of citric acid per sachet, and its product information names magnesium citrate as an active component. At the oxide figure above, 3.5 g is roughly 2 g of magnesium, taken to empty the bowel before an X-ray, endoscopy or surgery, so it is a different product from a daily supplement. For any liquid or powder, check the magnesium per serving and add it to your other sources.

How to read a UK magnesium glycinate label

Shopping for magnesium glycinate in the UK comes down to reading the label. UK rules require food supplement labels to state the amount of each vitamin or mineral in the product. The figure in the nutrition table is therefore the magnesium itself, often called elemental magnesium. The weight of the whole compound is a different and larger number. Roughly how much of each compound is magnesium:

• Oxide: about 60% (in one trial, 414 mg of magnesium oxide supplied 250 mg of magnesium)
• Citrate: roughly 11 to 16%, depending on the type of citrate
• Glycinate: about 14% (893 mg supplied 125 mg)
• L-threonate: about 7 to 8%

So a front-of-pack "magnesium bisglycinate 1,000 mg" gives you roughly 140 mg of magnesium, while "magnesium 200 mg (as bisglycinate)" means 200 mg of magnesium. The %NRV figure next to it compares that amount with the reference value used on UK food labels. Before you compare prices or doses, check the nutrition table.

How much magnesium should you take?

The NHS says adults need 300 mg of magnesium a day (men) or 270 mg (women), and it's found in foods such as spinach, nuts and wholemeal bread; our list of foods high in magnesium gives the amount in a typical portion. It also says 400 mg or less a day from supplements is unlikely to cause any harm. The European Food Safety Authority sets a lower upper level of 250 mg a day for magnesium from supplements, based on mild diarrhoea, so a supplement of around 200 mg sits within both.

Add up everything you take: a multivitamin, an electrolyte drink and a combination pack can each contain magnesium. If you use an electrolyte drink, our guide on whether you need electrolytes is worth reading alongside this one.

Bigger single doses are absorbed less efficiently. In a 1991 study, the share of magnesium absorbed with a meal fell from 65% at the lowest dose to 11% at the highest. A 2017 review of absorption studies found that your body takes up a larger share when the same amount comes in several small doses through the day rather than one large one.

Does it matter when you take glycinate or citrate?

Not much, and neither form has a best time of its own. Take it whenever you'll do so consistently. What makes more difference is taking it with a meal if your stomach is sensitive, splitting a larger dose across the day, and keeping it a few hours away from some antibiotics and bone medicines. Our guide to magnesium side effects covers the best time to take magnesium in full, including how to take it and how long it takes to work. If you're taking it for sleep, magnesium and sleep covers the evening timing the trials used.

Magnesium glycinate side effects, and who should avoid it

The most common side effect of any magnesium supplement is loose stools or diarrhoea, and it depends on the dose. Magnesium that isn't absorbed holds water in the bowel. The NHS links diarrhoea to doses above 400 mg, and EFSA based its 250 mg upper level on mild diarrhoea. Glycinate had a clean record in the 2025 trial, but that was a single four-week study. Our guide to magnesium side effects covers every form, how much is too much and who should avoid it.

Check with a GP or pharmacist before taking magnesium if:

• You have kidney disease. UK product information for licensed magnesium medicines rules them out in severe kidney impairment, because magnesium can build up in the blood. Don't take a supplement unless your kidney team advises it.
• You take any of the antibiotics or bone medicines above, or levothyroxine. The NHS asks people on alendronic acid to tell their doctor about supplements containing magnesium.
• You have taken a proton pump inhibitor such as omeprazole for more than a year. The MHRA has warned that low magnesium has been reported with long-term use, so ask your GP about a check before treating it yourself.
• You're pregnant or breastfeeding.

Do magnesium sprays, oils and bath salts work?

There's little good evidence that a meaningful amount of magnesium gets through the skin. The skin's outer layer is a barrier, and the magnesium in a chloride solution is in a charged form that crosses it poorly. A 2017 review in the journal Nutrients called the case for transdermal magnesium scientifically unsupported. In a 2017 pilot study, 25 people used a magnesium cream or a placebo cream for two weeks, and blood magnesium did not rise significantly overall, only in a subgroup of non-athletes. Epsom salt, which is magnesium sulphate, is licensed in the UK as a laxative when swallowed. A bath with it in is still a nice bath, but don't count it towards your magnesium.

What are the benefits of magnesium glycinate?

Long lists of magnesium glycinate benefits are easy to find online. In Great Britain, though, a supplement can only make the authorised health claims for magnesium, whatever form it comes in, and only if it provides enough magnesium. Those claims are that magnesium contributes to:

• a reduction of tiredness and fatigue
• normal energy-yielding metabolism
• normal functioning of the nervous system
• normal muscle function
• normal protein synthesis
• normal psychological function
• electrolyte balance
• the process of cell division
• the maintenance of normal bones and teeth

There's no authorised claim for glycine, and none for magnesium and sleep or blood pressure.

What does magnesium glycinate do for the body?

The magnesium in it does the work. The NHS describes magnesium as a mineral that helps turn the food we eat into energy, and the claims above are what a supplement can say about it. Glycinate is the carrier, so what magnesium bisglycinate is good for is the same as what any magnesium supplement is good for: adding to the magnesium you get from food. The NHS says you should be able to get all the magnesium you need from a varied, balanced diet. In the 2025 trial, nobody taking 250 mg of magnesium a day as bisglycinate reported stomach problems, though that was one four-week study.

Where Natura fits

Natura's Daily Magnesium (coming soon) is one capsule giving 200 mg of magnesium as glycinate, within both the NHS and EFSA guides for supplements. Magnesium contributes to a reduction of tiredness and fatigue and to normal muscle function. You'll find it among the single bottles. If you also use Daily Electrolytes, which has 100 mg of magnesium per sachet, or a Natura pack that includes magnesium, add the amounts together.