Magnesium is an essential mineral. Among other roles, it supports normal muscle and nerve function, energy metabolism and numerous enzyme reactions. These functions do not, however, mean that extra capsules provide an additional benefit when intake is already adequate.
How much magnesium is needed?
For adults aged 19 and over, the German Nutrition Society gives estimated daily intakes of 300 mg for women and 350 mg for men. These refer to total daily intake. They are not dosage recommendations for food supplements.
Wholegrain foods, pulses, nuts, seeds and green vegetables contribute to intake. The magnesium content of mineral water can also be relevant; the specific amount is stated on the label.
Symptoms are not conclusive evidence of deficiency
Muscle cramps or fatigue can have various causes. A single symptom does not prove magnesium deficiency. Persistent or pronounced symptoms require an assessment of diet, medical conditions and medicines together.
Blood magnesium is one possible test measurement, but it only partly reflects the body’s magnesium stores. This does not make the test worthless: what matters is medical interpretation alongside symptoms and medical history.
What matters when choosing a supplement?
- Check the amount of elemental magnesium. The weight of a magnesium compound is not the same as the amount of magnesium it contains.
- Add up all additional sources, including combined supplements and medicines containing magnesium.
- Take diarrhoea or abdominal discomfort seriously; more is not automatically better.
- If kidney function is impaired, do not start supplementation on your own.
- If you take medicines, such as certain antibiotics or osteoporosis treatments, ask your pharmacy about possible interactions and the product-specific intervals between doses.
Frequently asked questions
Does magnesium always help with cramps?
No. Whether supplementation is useful depends, among other things, on the cause and existing intake. Recurring symptoms should not be treated indefinitely on your own.
Do I need to meet my daily requirement with capsules?
No. Food counts towards total intake. A supplement adds to this when there is a justified need; it does not replace a varied diet.
Read more: magnesium deficiency, timing of intake and comparison of magnesium compounds.
