Magnesium is one of the minerals we often hear about in connection with tiredness, cramps and sleep. But what does it really do in the body, how much do we need and which supplement form is worth choosing? In this guide you will find the basics, what officially applies in the European Union and what studies show.
What magnesium does
Magnesium takes part in hundreds of enzyme reactions. It is needed for energy production, muscle and nerve function, protein synthesis and bone health. About half of the body’s stores are found in the bones.
Magnesium at a glance
| Question | Answer |
|---|---|
| How much do we need? | EFSA considers 350 mg a day adequate for men and 300 mg for women. |
| From food | Seeds, nuts, pulses, wholegrain cereals, green leafy vegetables. |
| Limit from supplements | 250 mg a day on top of food, mainly to avoid diarrhoea (limit set by the EU scientific committee). |
| Approved EU claims | Yes, for tiredness, muscles, the nervous system, bones and more (see below). |
Which foods provide it
| Food | About how much magnesium it provides |
|---|---|
| Pumpkin seeds, 30 g | about 150 mg |
| Cooked spinach, 1 cup | about 150 mg |
| Cooked beans, 1 cup | about 100–120 mg |
| Almonds, 30 g | about 80 mg |
| Oats, 40 g | about 55 mg |
| Dark chocolate 70–85%, 20 g | about 45 mg |
The values are indicative and vary with the variety and cooking. A diet with plenty of plant foods usually covers the needs.
What officially applies in the European Union
There are approved health claims for magnesium (Regulation 432/2012). Magnesium contributes to:
- a reduction of tiredness and fatigue,
- normal muscle function and normal functioning of the nervous system,
- electrolyte balance and normal energy-yielding metabolism,
- normal psychological function and normal protein synthesis,
- the maintenance of normal bones and teeth.
Which form to choose
In supplements, magnesium is always bound to another substance. The form affects how well it is absorbed and how well the gut tolerates it. Studies comparing forms are few, but in general:
- Oxide: provides a lot of magnesium per tablet, but is absorbed less well and causes diarrhoea more easily.
- Citrate: good absorption; in larger doses it can loosen the bowels.
- Bisglycinate: bound to the amino acid glycine; usually gentle on the stomach.
- Malate and taurate: organic forms, also well tolerated.
What the research shows
Sleep. A 2021 review found only 3 small trials in older adults with insomnia. With magnesium they fell asleep on average about 17 minutes faster, but the quality of the evidence was low. We cannot say with certainty that it helps sleep.
Cramps. According to a 2020 Cochrane review, magnesium probably does not reduce the common night cramps of older adults. For cramps in pregnancy the evidence is limited and contradictory.
Deficiency. Severe deficiency is rare. It is more common in people with type 2 diabetes, bowel conditions, high alcohol intake, older adults and those who take diuretics or stomach medicines (proton pump inhibitors) for a long time.
5 things worth knowing
- Food first. Seeds, nuts, pulses and green vegetables cover the needs of most people.
- Split the dose. If you have gut complaints, take magnesium in 2–3 doses during the day, with food.
- Mind your medicines. Magnesium reduces the absorption of some antibiotics, levothyroxine and osteoporosis medicines. Leave a gap of 2–4 hours.
- It is not a sleeping pill. For better sleep, a regular schedule, less caffeine in the afternoon and a dark room matter first.
- The kidneys remove the excess. That is why people with kidney disease should take magnesium only on medical advice.
Who should be careful
- People with kidney failure or other kidney disease.
- Anyone taking antibiotics, levothyroxine, osteoporosis medicines or diuretics.
- Pregnant and breastfeeding women, who should discuss any supplement with their doctor.
Magnesium in Active Woman products
My Magnesium combines three forms of magnesium: malate, bisglycinate and taurate. The 3 daily capsules provide 375 mg of magnesium and 1.4 mg of vitamin B6, i.e. 100% of the nutrient reference value. The product’s approved claims:
- Magnesium and vitamin B6 contribute to the reduction of tiredness and fatigue.
- Magnesium contributes to normal muscle function and normal functioning of the nervous system.
- Magnesium contributes to electrolyte balance.
If you have a sensitive gut, you can spread the capsules across the day’s meals. Food supplements should not be used as a substitute for a varied and balanced diet and a healthy lifestyle.
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Frequently asked questions
How much magnesium do I need?
EFSA considers 350 mg a day adequate for men and 300 mg for women, from all sources combined.
What time should I take it?
There is no «right» time. Many people prefer it with their evening meal. If you take medication, keep a gap of 2–4 hours.
Does it help with cramps?
For common night cramps, the evidence does not show a significant benefit. If cramps are frequent, talk to your doctor.
Can I take too much?
Not from food. From supplements, large doses mainly cause diarrhoea. In kidney disease, magnesium can build up.
Which form is best?
There is no single «best» form. Organic forms such as citrate and bisglycinate are absorbed and tolerated better than oxide.
Sources
- EFSA. Dietary reference values: magnesium and phosphorus, 2015.
- BfR. Proposed maximum levels for the addition of magnesium to foods including food supplements.
- Mah J., Pitre T. Oral magnesium supplementation for insomnia in older adults: a systematic review and meta-analysis. BMC Complementary Medicine and Therapies, 2021.
- Garrison S.R. et al. Magnesium for skeletal muscle cramps. Cochrane Database of Systematic Reviews, 2020.
- Regulation (EU) 432/2012. List of permitted health claims.
This article is for information purposes and is not a medical diagnosis, nor does it replace a doctor’s advice.
