Magnesium for Cramps: Does It Work? Best Type, Dose and What Helps

Does magnesium help cramps? The research

That doesn’t mean magnesium does nothing for muscles: it contributes to normal muscle function and electrolyte balance. But if your magnesium intake is already adequate, extra is unlikely to stop cramps.

What causes cramps?

Often there’s no clear cause. Common triggers include:

• muscle tiredness after exercise or long periods standing
• tight calf muscles and sitting or lying awkwardly
• getting older, pregnancy, and dehydration
• some medicines, such as diuretics and statins
• conditions such as diabetes, liver or kidney disease, and nerve problems

Who might benefit from magnesium?

• People with a low intake: diets low in wholegrains, nuts, seeds and greens. See signs of magnesium deficiency.
• People on medicines that lower magnesium, such as some diuretics or long-term proton pump inhibitors (like omeprazole). Your GP can check your level with a blood test.
• Heavy drinkers and people with gut conditions that affect absorption.

Best magnesium for cramps

Our Magnesium Glycinate Sleep Complex combines bisglycinate and citrate with glycine, L-theanine and botanicals, giving 290mg of magnesium per serving as a warm evening drink. Compare forms in types of magnesium.

How much to take

Adults need 270 to 300mg a day, mostly from food. If you supplement, 100 to 300mg a day is typical, and the NHS says 400mg or less a day from supplements is unlikely to cause harm. Give it four weeks, and if cramps haven’t changed, magnesium probably isn’t the answer for you. Speak to your GP first if you have kidney problems.

What helps cramps (NHS)

• During a cramp: stretch and massage the muscle. For a calf cramp, gently pull your toes up towards your shin.
• To prevent cramps: regular calf stretches, especially before bed.
• Afterwards: painkillers such as paracetamol or ibuprofen can ease lingering soreness.
• If these don’t help, a GP may review your medicines or, rarely, prescribe quinine.

Muscle soreness after exercise is different from cramp. See magnesium for muscle pain and CBD balm.

Cramping after heavy sweating? See electrolytes: do you need them?

When to see a GP

iSee a GP if cramps are frequent, affect your sleep or daily life, started after a new medicine, or come with muscle weakness, numbness or swelling. Get urgent help if one leg is swollen, red, warm and painful, as it could be a blood clot.

Related guides

• For what to do when cramps wake you, see leg cramps at night.
• Magnesium glycinate for muscles and cramps.
• Which magnesium is best: glycinate, citrate or threonate.
• Magnesium for sleep: best type, dose and timing.
• How to have an Epsom salt bath.
• For more on the form used in that cramp trial, read magnesium oxide explained.
• If you like a warm soak, our magnesium flakes guide explains what a bath can and can’t do.
• Does magnesium help eye twitching?
• For the best form for cramps and other goals, see our best magnesium supplement UK guide.
• Period cramps are different from leg cramps: see period pain relief for what helps.
• For twitches rather than cramps, see our guide to muscle twitching.
• If it’s an urge to move rather than a painful cramp, see magnesium for restless legs.
• Prefer a drink to a tablet? See magnesium powder vs tablets for how the formats compare.
• If cramps come at night, read when to take magnesium for an evening routine that fits around food and medicines.
• Magnesium threonate side effects and safety.
• Before reaching for a supplement, check your diet against our list of foods high in magnesium.
• Taking more magnesium than you need can upset your stomach; see the side effects of magnesium.
• Give it a few weeks of daily use; our magnesium timeline shows what the trials found.
• Taking glycinate? See how much magnesium glycinate to take daily, including how to read the label.
• If cramps are breaking up your sleep, our guide to tiredness on your period explains what helps.