Last updated: October 2026
Magnesium contributes to the maintenance of normal bones, and about 60% of the body’s magnesium is stored in bone. Studies link higher magnesium intake with slightly higher hip bone density, but a 2016 review found no link with fewer fractures. For bone health, calcium, vitamin D, weight-bearing exercise and not smoking matter most; magnesium is part of a balanced diet.
Below: how magnesium supports bone, what the research shows, how it fits with calcium and vitamin D, how much you need, and what helps prevent osteoporosis.
What magnesium does for bones
Magnesium is part of the bone structure itself, and it’s needed for the parathyroid glands, which control calcium levels, to work normally. It’s also needed to activate vitamin D. Magnesium has an authorised health claim: it contributes to the maintenance of normal bones and teeth.
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Magnesium Glycinate Sleep Complex
Magnesium Glycinate Sleep Complex is a berry drink powder with 290mg of magnesium a scoop from bisglycinate and citrate, plus glycine and L-theanine. Magnesium contributes to a reduction of tiredness and fatigue.
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View productWhat the research shows
| Study | What it found |
|---|---|
| Meta-analysis, 2016 (12 observational studies) | Higher magnesium intake was weakly linked with higher bone density at the hip and femoral neck, but not with fewer fractures |
| Review in older adults, 2022 | Higher magnesium intake was linked with higher hip bone density; no link with fractures was found, and long-term supplement trials are needed |
Most evidence is observational, which can’t show cause and effect. Magnesium supplements aren’t a treatment for osteoporosis.
Magnesium, calcium and vitamin D
| Nutrient | Role for bones | UK advice |
|---|---|---|
| Calcium | The main mineral in bone | 700mg a day for adults, mostly from food |
| Vitamin D | Helps absorb calcium | 10 micrograms a day supplement in autumn and winter for everyone. See vitamin D in winter |
| Magnesium | Part of bone; activates vitamin D | 300mg (men) or 270mg (women) a day, mostly from food |
You don’t need to take magnesium at a set ratio to calcium; a varied diet usually provides both. See magnesium vs zinc and magnesium for women.
How much you need
The NHS says adults aged 19 to 64 need 300mg of magnesium a day (men) or 270mg (women), and most people get enough from a varied diet: nuts, seeds, leafy greens, beans and wholegrains. If you take a supplement, 400mg a day or less is unlikely to cause harm. Long-term acid-reducing medicines can lower magnesium levels. See signs of magnesium deficiency and best magnesium supplement UK.
Our Magnesium Glycinate Sleep Complex gives 290mg of magnesium per serving from bisglycinate and citrate, as an evening drink. Magnesium supplements can reduce the absorption of some osteoporosis medicines (bisphosphonates), so take them at different times and ask your pharmacist. We don’t recommend our products during pregnancy or breastfeeding.
The FSA’s 10mg a day figure for CBD is precautionary advice rather than a legal limit, set while longer-term safety research continues. At Evopure we think it is a very cautious figure, and many adults use more. If you go above it, increase slowly, and check with your GP or pharmacist first if you take any medication.
What helps prevent osteoporosis
- Regular exercise, including weight-bearing activity such as walking, dancing or resistance training.
- Enough calcium and vitamin D.
- Not smoking, and keeping alcohol to 14 units a week or less.
- Talk to your GP about a bone density check if you’ve had a fracture from a minor fall, have a family history, or take long-term steroids.
Related guides
- Magnesium and calcium: should you take them together?, including the 2:1 ratio.
- Supplements for women over 40, from calcium to vitamin D.
- For the one trial on collagen and bone density, see collagen supplements: do they work?
- Calcium supplements and bone health.
- See also our evidence guide to glucosamine, which has no authorised health claims in GB.
- For a gentle everyday form, see our magnesium glycinate UK guide.
- Both nutrients play a part in normal bones: read should you take magnesium and vitamin D together?
- The different types of magnesium compared.
- If you’re in or past menopause, see magnesium for menopause and perimenopause for the best type and how much women need.
- For how much magnesium you need over 60 and the best type to take, see magnesium for older adults.
- Men get osteoporosis too; see supplements for men over 50 and 60 for vitamin D, calcium and when to ask a GP.
Sources 4
- Farsinejad-Marj M et al. Dietary magnesium intake, bone mineral density and risk of fracture: a systematic review and meta-analysis. Osteoporos Int, 2016.
- Groenendijk I et al. Impact of magnesium on bone health in older adults: a systematic review and meta-analysis. Bone, 2022.
- NHS. Preventing osteoporosis.
- NHS. Vitamins and minerals: magnesium.
