Best Magnesium Supplement UK: How to Choose by Form, Dose and Goal

Is our Magnesium Glycinate Sleep Complex right for you?

We make one magnesium product, so here’s an honest view of where it fits. Choose by format and routine first (checked against our product page, October 2026).

What’s in it. A berry-flavoured drink powder with magnesium bisglycinate and citrate, glycine and L-theanine, plus oat straw, hops, chamomile and passionflower extracts, sweetened with stevia. One 4.75g scoop gives 290mg of magnesium, and a pouch holds 30 servings. See also the best magnesium drink in the UK.

The label maths. That 290mg is elemental magnesium, not the compound’s weight. The NHS says adults need 300mg a day (men) or 270mg (women), so one serving gives about half a man’s need and a little over half a woman’s, with food making up the rest, well inside the NHS guide of 400mg a day or less from supplements. Magnesium contributes to a reduction of tiredness and fatigue, to normal muscle function and to normal psychological function.

It suits you if you’d rather drink your magnesium, like a drink at the end of the day, and want a well-absorbed form at a moderate dose.

Choose something else if:

• you’d rather swallow a tablet or capsule: a plain glycinate or citrate will suit you better.
• you want a higher dose than 290mg per serving: choose a plain glycinate or citrate, staying within 400mg a day from supplements.
• you want a daytime top-up without herbal extracts, or magnesium for constipation (citrate is the usual choice).
• you’re pregnant or breastfeeding, under 18, have kidney disease or take regular medicines. We don’t recommend our products during pregnancy or breastfeeding, and they’re for adults (18+) only. If you take any medication, check with your GP or pharmacist first.

How to compare value: a pouch holds about 8,700mg of magnesium (30 x 290mg), so divide its price by 87 for the cost per 100mg and compare any tablet with the value sum below. There’s one size, so Subscribe and Save is the cheapest way to buy: it lowers the price of every order, and you can skip, pause or cancel any time.

What you get with Evopure:

• Our CBD products: every batch third-party tested at ISO 17025 labs; request a batch report on our lab testing page.
• Made in the UK, vegan and alcohol-free.
• Our Sleep CBD Oil, in the box below, is broad spectrum and THC free, confirmed on each batch’s lab report, and on the FSA public list, linked to validated applications.
• Tracked Royal Mail UK delivery, dispatched the same day if you order before 3pm Monday to Thursday (delivery details).
• Unopened, unused items can be returned within 14 days of delivery, once we’ve approved the return (returns policy).

These are food supplements, not medicines, and we don’t claim they treat any condition. Ready to choose? Pick the Magnesium Glycinate Sleep Complex for a magnesium drink at the end of the day, the Reishi Mushroom Adaptogenic Complex if you’d prefer a hot chocolate (cacao contains a little natural caffeine), or the Sleep CBD Oil if you’d like a few drops under the tongue as part of your evening.

The FSA’s 10mg a day figure is precautionary advice rather than a legal limit, set while longer-term safety research continues. At Evopure we think it is a very cautious figure, and many adults use more. If you go above it, increase slowly, and check with your GP or pharmacist first if you take any medication.

Quick picks: the best magnesium by goal

There is no single best magnesium for everyone. The right choice depends on why you want it, how your stomach copes, and when you will take it. Here is the short version.

Stocking up for winter? Our Black Friday supplement deals run from 27 to 30 November.

Whichever form you choose, magnesium contributes to a reduction of tiredness and fatigue, to normal psychological function, to normal functioning of the nervous system and to normal muscle function. Those are the health claims allowed in Great Britain. A product that promises to cure anxiety, insomnia or migraines is going further than the rules allow.

For a deeper look at the three most compared forms, see glycinate vs citrate vs threonate, or our full guide to the types of magnesium.

How we chose these picks

We make one magnesium product, so rather than ranking other brands’ products we haven’t tested ourselves, we judged each form and format against the same tests we used when we built our own blend. Use them on any tub or box you are looking at.

1. Absorption evidence. Forms that did well in human studies, such as citrate and amino acid chelates like glycinate, over mainly-oxide tablets (see forms compared).
2. Elemental magnesium stated in mg. If the label only gives the weight of the compound, you can’t tell what you are getting.
3. A sensible dose. Within the NHS guide of 400mg a day or less from supplements. The European Food Safety Authority sets a more cautious upper level of 250mg a day for magnesium added as supplement salts, not counting the magnesium naturally in food.
4. No needless fillers. Few colours, bulking agents and sugars, and a reason for every extra ingredient.
5. Independent testing. A certificate of analysis from an accredited lab, ideally ISO 17025.
6. Honest labelling. Only the authorised health claims, and no promises to cure or treat anything.
7. Practical fit. A format you will actually take every day, vegan if you need it, and a fair cost per 100mg of magnesium.

The full 8-point checklist below turns these into questions you can ask of any label.

Magnesium for an evening routine

Choosing magnesium mainly for sleep? Our full guide to the best magnesium for sleep compares every form for bedtime, with dosing and timing. If you just want the label basics for an evening supplement, look for:

• Form: glycinate (bisglycinate) first; citrate if your stomach copes with it.
• Dose: roughly 100 to 300mg of elemental magnesium per serving, so your total from supplements stays at 400mg a day or less.
• Timing and format: something you will take every evening, such as a capsule or a warm drink. Consistency matters more than the exact hour.
• No melatonin: in the UK melatonin is a prescription-only medicine, so a UK food supplement shouldn’t contain it. Our guide to melatonin in the UK explains why.
• Extras with a reason: glycine and L-theanine are common partners; herbs such as chamomile or passionflower have no authorised health claims.

Our Magnesium Glycinate Sleep Complex was built for that kind of evening routine. It isn’t a sleeping pill and we don’t claim it will make you sleep. Magnesium contributes to a reduction of tiredness and fatigue and to normal psychological function.

iFor an evening routine, most people choose magnesium glycinate (often labelled bisglycinate), because it is well absorbed and gentle on the stomach. Magnesium isn’t a treatment for insomnia: if poor sleep keeps going, speak to your GP.

For timing, see the best time to take magnesium and whether magnesium makes you sleepy. Comparing magnesium with other options? Read our guides to natural sleep aids in the UK and glycine for sleep.

Best magnesium for stress and anxiety

Glycinate is again the usual choice, simply because it is gentle enough to take every day. Magnesium contributes to normal psychological function and to normal functioning of the nervous system, which is why people under pressure often look at it.

The evidence for anxiety is promising but weak. A University of Leeds systematic review of 18 studies found hints of a benefit in people already prone to anxiety, mostly in small, poor-quality trials, and concluded that better trials are needed. Threonate is often sold as the “brain” form, but there is no good head-to-head evidence that it beats glycinate for stress.

Magnesium is not a treatment for an anxiety disorder. If anxiety is affecting your daily life, your GP can refer you for proven support. Our guide to magnesium for anxiety goes through the studies in more detail.

Best magnesium for muscle cramps

If you want to try magnesium for cramps, choose citrate or glycinate rather than oxide, because they are better absorbed. Magnesium contributes to normal muscle function, and getting enough matters.

Be realistic, though. A 2020 Cochrane review of 11 trials found that, for the common night-time leg cramps of older adults, magnesium made little or no difference to how often cramps happened. The trials in pregnancy gave conflicting results. So magnesium may suit you best if your diet is low in it, rather than as a cramp cure.

iThe NHS suggests regular calf stretches to help prevent cramps, and says to see a GP if cramps disturb your sleep, last longer than 10 minutes, or come with numbness or swelling. More in our guides to magnesium for cramps, leg cramps at night and magnesium for muscle pain.

Every form of magnesium compared

Magnesium in supplements is always bound to something else. That partner changes how much actual (elemental) magnesium you get, how well it absorbs, and how your gut reacts.

Percentages are calculated from each compound’s molecular weight, so real products vary a little depending on water content and blends.

Why oxide looks strong on paper

Oxide packs the most magnesium by weight, which is why cheap tablets can print a big number on the front. In a US study of four preparations, only about 4% of the magnesium in oxide was absorbed, while chloride, lactate and aspartate did clearly better. A 60-day randomised trial at the University of Reading found that citrate and an amino acid chelate were absorbed better than oxide, with citrate giving the highest blood levels.

What about sprays, flakes and baths?

A 2017 review of the research concluded that the idea of absorbing meaningful magnesium through the skin is scientifically unsupported. A warm bath with flakes can still be a lovely part of an evening; just don’t count it towards your daily intake.

How to choose: an 8-point checklist

1. Elemental magnesium per serving, in mg. This is the number that matters. “1,000mg magnesium bisglycinate” contains only about 140mg of actual magnesium. Look for the magnesium line in the nutrition table and its %NRV (the reference value is 375mg).
2. The form, named clearly. Glycinate, bisglycinate, citrate or malate, rather than just “magnesium” or a blend that is mostly oxide.
3. A dose that fits your needs. Adults need 300mg a day (men) or 270mg (women), and most of that should come from food. A supplement is a top-up, and the NHS says 400mg a day or less from supplements is unlikely to cause harm.
4. Extra ingredients with a reason. Check what each one is for and how much is in it. Herbs such as passionflower or ashwagandha have no authorised health claims, so be wary of big promises about them.
5. Few unnecessary extras. Watch for sugars and sweeteners, especially in gummies, plus colours and bulking agents.
6. Independent testing. Ask for a certificate of analysis from an accredited lab (ISO 17025 is the standard to look for). A good brand will share it.
7. Price per mg of elemental magnesium. Not price per tub or per capsule. See the next section.
8. Honest claims and a format you will stick to. Only the authorised claims above are allowed. Then pick capsules, tablets, powder or gummies that suit your day.

Many supplements fail on at least one of these. See why your magnesium might not be working.

How to compare value

Compare the cost of 100mg of elemental magnesium, not the cost per tablet. The sum is simple:

Then weigh that against the form. A cheap oxide tablet may win on cost per mg but lose on absorption, while glycinate and citrate contain less magnesium by weight but are absorbed better. If a product hides its elemental figure, you can’t work out its value, which is a red flag in itself.

Why are some magnesium supplements so expensive?

Mostly because of the form. Bisglycinate is only about 14% magnesium and L-threonate about 7 to 8%, so a useful dose needs far more powder: bigger or more capsules per serving. Oxide is about 60% magnesium and cheap, so one small tablet can print a big number on the front.

Extra ingredients, lab testing, formats such as gummies and branding add to the price too. Paying more is worth it only for a better-absorbed form, a clearly labelled elemental dose or ingredients you actually want, so check the cost per 100mg of elemental magnesium first. Threonate costs the most per mg of magnesium; see whether L-threonate is worth the price.

Magnesium supplements UK: tablets vs powder vs capsules vs sprays

UK magnesium comes in five main formats. The table in our section above compares powders, tablets, capsules and gummies by routine. Tablets are cheap but can be large, with more binders. The fifth format, sprays and oils, makes a pleasant massage ritual, but absorption through the skin is unproven, so don’t count it towards your intake. Pick the form first, then the format you will stick with.

The form matters more than the format. See magnesium powder vs tablets, whether a magnesium spray is worth it, and why a magnesium complex combines more than one form.

Do you actually need a magnesium supplement?

Food comes first. The NHS says adults aged 19 to 64 need 300mg of magnesium a day (men) or 270mg (women), and that you should be able to get all you need from a varied, balanced diet: nuts, seeds, leafy greens such as spinach, beans and wholegrains such as wholemeal bread.

A supplement makes most sense if your diet is light on those foods, your GP has found low levels, you take a medicine that can lower magnesium (see below), or you want a consistent evening routine. If your diet already covers your needs, extra may make little difference. Women’s needs and the menopause years are covered in our guide to magnesium for women.

How much to take

The NHS says having 400mg a day or less of magnesium from supplements is unlikely to cause harm, while taking more than 400mg for a short time can cause diarrhoea.

The European Food Safety Authority is more cautious: its upper level for magnesium from supplements and fortified foods is 250mg a day, not counting the magnesium naturally in food. A serving that sits between 100 and 250mg keeps you inside both. For daily amounts by age and sex, see how much magnesium per day.

In practice, that makes a supplement of roughly 100 to 300mg of elemental magnesium a sensible top-up for most adults, especially if your diet is light on magnesium-rich foods. Wondering whether you are low? Our guide to the signs of magnesium deficiency explains what to look out for and when a blood test makes sense.

Give it time: our guide to how long magnesium takes to work covers what to expect in the first weeks.

Why your magnesium might not be working

1. The form is poorly absorbed. Mainly-oxide tablets look strong on paper, but little gets in (see forms compared).
2. Too much at once. Large single doses, especially of oxide or citrate, can loosen stools. Split the dose or choose glycinate.
3. The number on the front isn’t the magnesium. Check the elemental mg in the nutrition table (point 1 of the checklist).
4. You weren’t low to begin with. If your diet already provides enough, a supplement may change little. See the signs of magnesium deficiency.
5. Something is lowering it. The MHRA has reported low magnesium with long-term use of acid-reducing PPIs such as omeprazole. Very high-dose zinc can also get in the way: in one metabolic study, 142mg of zinc a day reduced magnesium absorption.
6. Taken alongside certain medicines. Some antibiotics and osteoporosis medicines need spacing from magnesium. See who should be careful.
7. Expecting too much, too soon. Magnesium isn’t a sleeping pill. Take it daily for a few weeks before you judge it.

Who should be careful

• Kidney disease: don’t take magnesium supplements without medical advice.
• Osteoporosis medicines (bisphosphonates): the NHS says to tell your doctor if you take supplements containing magnesium with alendronic acid, and to wait at least 30 minutes after a dose before taking anything else by mouth.
• Some antibiotics: tetracyclines such as lymecycline can be affected by supplements containing magnesium, and quinolones such as ciprofloxacin need spacing away from antacids and mineral supplements. The NHS also asks you to tell your doctor about any vitamins or supplements before you start ciprofloxacin. Ask your pharmacist how to time them.
• Long-term acid-reducing medicines (PPIs, such as omeprazole): the MHRA has reported low magnesium levels with prolonged use, mostly after a year or more. Speak to your GP, who may want to check your levels, rather than guessing a dose yourself.
• Pregnancy and breastfeeding: speak to your midwife or GP. We don’t recommend our products during pregnancy or breastfeeding.
• Children: our products are for adults (18+) only. Ask a GP or pharmacist before giving a child any magnesium supplement.
• Side effects: loose stools are the most common, mainly with oxide, citrate or high doses. See magnesium side effects.

iIf you take any regular medicine, check with your pharmacist before adding magnesium.

Where our magnesium fits

Our Magnesium Glycinate Sleep Complex was built around the checklist above: bisglycinate and citrate for 290mg of elemental magnesium per serving (77% of the NRV), with no threonate. Its chamomile, passionflower, hops and oat straw carry no authorised health claims, so we make none for them.

Related guides

• Our magnesium citrate guide.
• Considering a daytime form? Read our guide to magnesium malate.
• See also our honest guide to magnesium taurate in the UK.
• Not sure why oxide tablets look so strong on paper? See how much magnesium is really in magnesium oxide.
• Need help with constipation? Read magnesium for constipation.
• If you are thinking of buying more than one tub at a time, see is Black Friday a good time to stock up on supplements?
• Choosing for a sensitive gut? Our guide to magnesium for bloating compares citrate, oxide and glycinate.
• Thinking about ashwagandha instead? See ashwagandha vs magnesium.
• For a men’s view of form, dose and safety, see the best magnesium for men.
• Minerals like magnesium aren’t farmed, so an “organic magnesium” label is worth a closer look; see best organic supplements UK.
• Comparing minerals rather than forms? Our magnesium vs zinc comparison sets them side by side.
• Magnesium at Home Bargains: forms and amounts.
• Vitabiotics Ultra Magnesium: what’s in it and how to take it.
• Checking a specific brand? See our facts page on Wild Nutrition magnesium.
• For a brand-by-brand label check, see Solgar magnesium explained.
• Some products online use magnesium orotate, which is not on the GB list of permitted forms; our magnesium orotate guide explains why.
• For one brand’s seawater capsule explained label by label, see Together Health magnesium.
• Brand-by-brand label checks: Bioglan magnesium.
• Shopping at Boots? See Boots magnesium: the own-brand range and label maths.
• Buying in store? We checked the labels on Superdrug magnesium too.
• Buying at the supermarket? We checked the labels on Tesco magnesium.
• For one gummy brand’s label maths in detail, see Novomins magnesium gummies.
• For one liquid option, see Zooki magnesium sachets and capsules.
• Looking at a specific brand? See Natural Vitality Calm for its UK range, magnesium per serving and directions.
• Looking at a particular brand? See Viridian magnesium for forms and doses, checked at the source.
• Checking a specific brand? Read Healthspan magnesium: range, forms and how much you get.
• Shopping at a supermarket? See Tesco and Aldi magnesium.
• Comparing practitioner brands? See our factual guide to BioCare magnesium.
• We’ve also checked the Natures Aid magnesium range, from glycinate to calcium, magnesium and zinc.
• Brand by brand, we’ve also set out what’s in Nutravita magnesium.
• We have also checked the labels of individual brands, including Pure Encapsulations magnesium.
• Prefer a drink to tablets? See magnesium glycinate powder in the UK: what to look for.
• Pairing magnesium with a winter vitamin D supplement? Read magnesium and vitamin D together.
• Thinking about a multi-form blend? Our guide to the 12 in 1 magnesium complex shows how to check the elemental magnesium.
• For restless legs, see which magnesium to try for restless legs, and why a ferritin test comes first.
• For women in perimenopause or menopause, see the best magnesium for menopause.
• Buying for an older parent? Magnesium for older adults covers amounts, gentle forms and safety checks.
• Looking at a practitioner brand? Our Cytoplan magnesium bisglycinate page works through its label: 200mg of magnesium in two capsules.
• Looking at Heights? Our Heights magnesium page works through its label: 300mg of magnesium in two capsules, from glycinate buffered with oxide.