What magnesium does
Magnesium contributes to normal muscle function, to the normal functioning of the nervous system and to normal psychological function. It also contributes to the reduction of tiredness and fatigue, to normal energy-yielding metabolism and to the maintenance of normal bones.
How much you need
The NHS puts adult needs at 300mg a day for men and 270mg a day for women. Most people can get this from a varied diet, and 400mg or less a day from supplements is unlikely to cause harm. Higher doses can cause diarrhoea.
Where to find it
Magnesium is found in green leafy vegetables such as spinach, nuts and seeds, beans and lentils, and wholegrain bread and cereals.
What about sleep?
You will often read that magnesium helps you sleep. There is no authorised health claim for that, so we will not make one. What magnesium does contribute to is the normal functioning of the nervous system and normal psychological function.
For better sleep, the NHS points to habits that work for most people:
- Go to bed and wake up at the same times every day.
- Keep the bedroom dark, quiet and at a comfortable temperature.
- Avoid tea, coffee and energy drinks in the hours before bed.
- Put screens away before bed — their light can keep you awake.
Before you start
If you have kidney problems, or take antibiotics or other regular medicines, ask your doctor or pharmacist before taking magnesium. Sleep problems that last for weeks and affect your days are a reason to see a doctor.
This information is for general education and does not replace advice from your doctor or pharmacist.
Sources
We cite public health authorities only.
