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    Ingredient evidence

    Magnesium glycinate

    The most recommended supplement in women's health, and one of the few where the recommendation is broadly reasonable. Here is what it does, what it does not, and how to take it without wasting money.

    Also sold as: magnesium bisglycinate, chelated magnesium.

    Our read of the evidence

    Reasonable evidence

    Some good human data, but not enough to be certain.

    Genuinely useful if you are low in magnesium or sleeping badly. Not a sedative, and not a cure for anxiety.

    What the evidence actually shows

    Magnesium is an essential mineral involved in several hundred enzyme reactions, including nerve signalling and muscle relaxation. UK intake data consistently shows a meaningful proportion of women fall below the reference nutrient intake, particularly those eating less green veg, nuts and wholegrains. Correcting a genuine shortfall is where most of the benefit sits.

    For sleep, trials in older adults show modest improvements in sleep quality and time to fall asleep. The effect sizes are small and the studies are not large. It is fair to describe magnesium as sleep-supportive; it is not fair to describe it as a sleeping pill.

    For premenstrual symptoms, several small trials suggest magnesium reduces fluid retention, breast tenderness and mood symptoms, often better when combined with vitamin B6. The trials are old and small, but the risk of trying it is low.

    For migraine, the evidence is stronger than most people realise: magnesium is one of the few supplements with enough data to appear in headache guidelines as a preventive option, usually at higher doses than a general wellbeing product provides.

    Why the form matters more than the brand

    Magnesium oxide is cheap and poorly absorbed. Most of it stays in the gut, which is why it works as a laxative and why so many people conclude magnesium 'upsets my stomach'. Glycinate, citrate and malate are all better absorbed. Glycinate is the gentlest and the one usually chosen for evening use.

    Read the elemental magnesium figure, not the compound weight. A capsule listing '1,000mg magnesium bisglycinate' may contain only 100-140mg of actual magnesium. This single detail explains most of the price difference between products that look identical on the shelf.

    How to take it.

    Typical dose
    200-400mg elemental magnesium daily
    Form
    Glycinate or bisglycinate for sleep and calm; citrate if constipation is also an issue
    Timing
    Evening, with or after food
    Worth knowing
    Start at the lower end. The UK safe upper level for supplemental magnesium is 400mg a day; higher doses are used clinically but should be a decision made with a prescriber.

    What it will not do.

    • It will not sedate you or reliably knock you out
    • It will not treat clinical anxiety or depression
    • It will not replace HRT for perimenopausal sleep disruption
    • It will not do anything noticeable if your magnesium status is already fine

    Who should avoid it.

    • You have reduced kidney function - magnesium is cleared by the kidneys and can accumulate
    • You have a heart block or are on medication for a slow heart rate
    • You are already taking a prescribed magnesium preparation

    Raise with a prescriber

    • Reduces absorption of some antibiotics (tetracyclines, quinolones) - separate by at least two hours
    • Reduces absorption of levothyroxine - separate by four hours
    • May add to the effect of bisphosphonates and some blood pressure medicines

    Products containing magnesium glycinate.

    Everything below is stocked in the UK. Compare on the active dose and the cost per day rather than the size of the pack.

    Products containing Magnesium glycinate
    ProductKey activesFormPricePer dayBest for
    Cycle Support PackPerelelVitamin B6, Magnesium glycinate, Calcium, ChasteberryCapsule£42/month£1.50PMS and mild PMDD, Regular menstrual cycles, Wanting cycle-aware support
    Magnesium EaseThe Nue Co.Magnesium chloride (topical)Spray£35£1.17Restless legs, Sleep-onset insomnia, Post-workout recovery
    Magnesium Glycinate 400BetterYouMagnesium bisglycinate 400mgCapsule£1860pSleep-onset insomnia, Muscle cramps, Perimenopausal sleep changes
    Peri-BoostMPowderSage, Maca, B-complex, Magnesium, Vitamin D3Powder£55/month£1.83Perimenopause, Hot flushes, Perimenopausal fatigue
    Liposomal Magnesium BisglycinateElle SeraMagnesium bisglycinate (liposomal)Liquid£40.00£1.33Trouble falling asleep or staying asleep, Muscle cramps, restless legs or night-time tension, Cycle-related tension and irritability, Anyone who has found other magnesium forms upsetting to the gut
    Cycle ElixirARTAHMyo-inositol, Vitamin B6 (P5P), Magnesium, ChasteberryPowder£48£1.60PCOS, PMDD, Irregular cycles
    Wild Nutrition Food-Grown MagnesiumWild NutritionMagnesium (food-grown)Capsule£24.0080pBroken sleep, Night-time cramps
    Menopace OriginalVitabioticsB vitamins, Vitamin D, ZincTablet~£10-Filling nutrient gaps in perimenopause, Women who want a non-botanical option
    Perimenopause Multi-NutrientHealth & HerSage, Red clover, Vitamin B6Capsule~£24-Early perimenopause alongside lifestyle change, Women not yet on HRT
    Wild Nutrition Endo SupportWild NutritionMagnesium, B vitamins, Botanical blendCapsule£46.50£1.55Nutritional support alongside specialist care
    Wild Nutrition Premenstrual SupportWild NutritionMagnesium, Vitamin B6, Botanical blendCapsule£41.00£1.37Broken sleep, Night-time cramps, Premenstrual symptoms, as a time-limited trial
    Wild Nutrition Menopause ComplexWild NutritionMagnesium, Vitamin D, B vitamins, BotanicalsCapsule£42.00£1.40Broken sleep, Night-time cramps, UK winter
    DR.VEGAN Magnesium GlycinateDR.VEGANMagnesium bisglycinateCapsule£19.9967pBroken sleep, Night-time cramps
    DR.VEGAN PMS HeroDR.VEGANChasteberry, Vitamin B6, Magnesium, AshwagandhaCapsule£26.9990pPremenstrual symptoms, as a time-limited trial, Broken sleep, Night-time cramps
    Bare Biology Ready & Rested Magnesium BisglycinateBare BiologyMagnesium bisglycinate 375mgCapsule£34.9958pBroken sleep, Night-time cramps
    ARTAH Essential MagnesiumARTAHMagnesium blendCapsule£24.00-Broken sleep, Night-time cramps
    Together Health Marine MagnesiumTogether HealthMarine-sourced magnesiumCapsule£8.9530pBroken sleep, Night-time cramps
    Viridian High Potency Magnesium BisglycinateViridian NutritionMagnesium bisglycinateCapsule£16.0554pBroken sleep, Night-time cramps
    Igennus Triple Magnesium ComplexIgennus Healthcare NutritionMagnesium citrate, bisglycinate, taurateTablet£16.9556pBroken sleep, Night-time cramps

    Prices are the brand's UK list price at the time of writing and change often. Cost per day is calculated from pack size and the label's daily serving, and is shown only where both are published.

    Common questions.

    Is magnesium glycinate better than magnesium citrate?

    For sleep and calm, yes: glycinate is gentler on the gut and the glycine itself is mildly calming. Citrate is the better choice if you also want help with constipation, because it draws water into the bowel.

    How long before magnesium works for sleep?

    People who respond usually notice a difference within one to two weeks. If nothing has changed after a month at 300-400mg, magnesium is not your limiting factor and continuing is unlikely to help.

    Can I take magnesium during perimenopause?

    Yes, and it is a sensible thing to try for sleep, cramps and restless legs. It does not replace hormone therapy, and it will not touch hot flushes.

    Can you take too much magnesium?

    Yes. Excess supplemental magnesium causes diarrhoea first, and in people with impaired kidney function it can build up to dangerous levels. Stay at or below 400mg supplemental daily unless a clinician advises otherwise.

    A supplement is not clinical care.

    If symptoms are affecting your work, your sleep or your relationships, the useful next step is an assessment rather than another purchase. Our check-in takes three minutes and points you to the right kind of clinician.

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    Food supplements are not medicines and are not intended to diagnose, treat or cure any condition. They should not replace a varied diet or prescribed treatment. If you are pregnant, breastfeeding, taking medication or managing a diagnosed condition, check with a pharmacist or clinician before starting anything on this page. We do not accept payment for inclusion or placement. Where a link earns us a commission we say so on the product page. Last reviewed 27 August 2026.