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Can You Take Zinc and Magnesium Together? Doses, Timing, ZMA
Yes. You can take zinc and magnesium together: no human study has found that either mineral blocks the other, and the pair sits in one tablet in many products. The UK amounts (how much zinc a day) are 9.5 mg of zinc a day for men and 7 mg for women, and 300 mg of magnesium for men and 270 mg for women; the NHS adds "Do not take more than 25mg of zinc supplements a day unless advised to by a doctor" and that "Having 400mg or less a day of magnesium from supplements is unlikely to cause any harm."1 Take them with a meal if zinc on an empty stomach makes you feel sick. This page is a spoke of the Wellgard zinc guide and the vitamins and minerals guide.
- UK lines: zinc 25 mg a day from supplements; magnesium 400 mg
- Sleep: eight small zinc trials and a melatonin-driven mix; three magnesium trials, about 17 minutes sooner to sleep
- ZMA: zinc, magnesium and vitamin B6; its one placebo-controlled trial found no hormone change
Can you take zinc and magnesium together?
Yes. The interaction evidence for zinc concerns iron, which can lower zinc absorption "if given together in a supplement, whereas no effect is observed when the same amounts are present in a meal as fortificants", and calcium, where the older meal studies point both ways.2 For magnesium there is no human trial either way, so the spacing some guides suggest, including what should you not take with magnesium, is a precaution rather than a trial result. Zinc on an empty stomach can cause nausea: in a six-week trial of 150 mg a day, far above any supplement amount, symptoms were reported by 84% of women and 18% of men, so a combined tablet goes with food.3 Above 25 mg of zinc a day for months the NHS warns that "Taking high doses of zinc reduces the amount of copper the body can absorb. This can lead to anaemia and weakening of the bones."1 Anyone with kidney disease should not take magnesium without medical advice; in pregnancy and breastfeeding both minerals stay within the NHS amounts, and children have them only on a GP's advice.
What are zinc and magnesium each good for?
Each has its own authorised wordings in the Great Britain register, and none exists for the pair.4 Zinc contributes to the normal function of the immune system, to the maintenance of normal skin, hair, nails, bones and vision, to normal cognitive function, to normal fertility and reproduction, to the maintenance of normal testosterone levels in the blood and to the protection of cells from oxidative stress. Magnesium contributes to normal muscle function, to normal functioning of the nervous system, to normal psychological function, to normal energy-yielding metabolism, to the maintenance of normal bones and to a reduction of tiredness and fatigue. Neither list includes sleep, and only zinc's includes testosterone. Signs of zinc deficiency and the signs of low magnesium set out who runs short of each.
What is the best time to take zinc and magnesium?
No trial compares morning with evening for either mineral, so timing is about tolerance and habit. Zinc goes with a meal to avoid nausea.3 Magnesium is often taken with the evening meal; consistency matters more than the clock, and more than 400 mg in a day can cause diarrhoea.1 Both need a gap from a short list of medicines, set out on what should you not take with zinc and the magnesium interactions page. When is the best time to take zinc has the detail.
| Zinc | Magnesium | |
|---|---|---|
| UK daily amount from food | 9.5 mg men, 7 mg women | 300 mg men, 270 mg women |
| NHS line for supplements | Not more than 25 mg a day unless a doctor advises | 400 mg or less a day unlikely to cause harm |
| With food? | Yes, to avoid nausea | Either; a meal is the common habit |
| Keep a gap from | Larger iron doses; quinolone and tetracycline antibiotics; penicillamine | Tetracycline and quinolone antibiotics; bisphosphonates; levothyroxine |
| Each other | No human study shows interference; the same tablet is fine |
Should you take zinc and magnesium before bed, and do they help you sleep?
Plenty of people take the pair at night and report sleeping better, and plenty no change; those are accounts, not trials. For zinc, a 2024 systematic review found eight randomised trials of 10 to 73.3 mg a day for 4 to 48 weeks: most reported better sleep quality in adults, zinc "did not have a significant effect on sleep disorders", and the reviewers found "no consensus".5 The best-known trial gave 43 care-home residents with insomnia, average age 78, a nightly mix of 5 mg melatonin, 225 mg magnesium and 11.25 mg zinc for eight weeks; their sleep-quality score improved by 6.8 points more than placebo (95% CI 5.4 to 8.3), a result that cannot be attributed to the zinc or the magnesium, and melatonin in the UK is "available on prescription only".6, 7 For magnesium alone, a 2021 meta-analysis pooled three trials in 151 older adults with insomnia: they fell asleep 17.36 minutes sooner than on placebo (95% CI 7.44 to 27.27 minutes), total sleep time rose by 16.06 minutes without reaching significance, every trial was at moderate to high risk of bias, and the evidence was graded low to very low quality.8 Magnesium contributes to normal psychological function and normal functioning of the nervous system; those three trials are its placebo-controlled sleep evidence. Does magnesium help you sleep, does zinc help you sleep and which vitamin deficiency affects sleep have the detail.
What is ZMA, and what did its trials find?
ZMA is a combination of zinc, magnesium and vitamin B6 sold mainly to gym-goers. Its placebo-controlled trial is a 2004 study in which 42 resistance-trained men took ZMA or placebo before sleep through eight weeks of standardised training: serum zinc rose by 11 to 17%, which was not significant, and there were no significant differences between the groups in anabolic or catabolic hormones, body composition, strength or muscular endurance.9 The zinc-only testosterone studies, four young men whose levels fell on a zinc-restricted diet and nine older men short of zinc whose levels rose on repletion, neither with a placebo group, are set out on what does zinc do for men; no placebo-controlled trial shows a rise in men whose zinc is normal. The register sentence, "Zinc contributes to the maintenance of normal testosterone levels in the blood", belongs to zinc alone; magnesium has no testosterone wording, and vitamin B6 contributes to the regulation of hormonal activity.4 Taken every day, the totals are what matter: read the elemental figures on the label, add any multivitamin, and keep zinc within the NHS 25 mg line and magnesium within 400 mg.1
What about calcium or vitamin D with zinc and magnesium?
Calcium, magnesium and zinc are sold as a trio, and the only rule is to count the zinc. The calcium-zinc evidence is mixed: in a 1980 tracer study, adding calcium as milk products improved zinc absorption from a wholemeal-bread meal.10 The two-hour gap suggested on do you need a calcium supplement is a precaution, not a trial finding. Vitamin D has no documented interaction with zinc or magnesium in the NHS pages or these trials, and the three are commonly combined (what you should not take with vitamin D has vitamin D's own list); the NHS says 10 micrograms a day "will be enough for most people" and "Do not take more than 100 micrograms (4,000 IU) of vitamin D a day as it could be harmful."11 Can you take too much vitamin D has the detail.
Frequently asked questions
Do you need zinc to absorb magnesium?
No. Each mineral is absorbed on its own, and no study shows one is needed for the other.
Can you take magnesium glycinate and zinc picolinate together?
Yes. The form changes the weight of the compound, not the rule: read the elemental figures on each label and keep the zinc within 25 mg a day.1 Which magnesium is best compares the magnesium forms.
Which foods give both zinc and magnesium?
Seeds, nuts and wholegrains. In the UK food tables, pumpkin seeds carry 270 mg of magnesium and 6.6 mg of zinc per 100 g, so a 30 g handful gives about 81 mg and 2 mg; plain cashews carry 270 mg and 5.9 mg per 100 g, so 30 g gives about 81 mg and 1.8 mg.12 What foods contain magnesium has the full table.
What happens if you take zinc and magnesium every day?
Within the NHS lines, nothing the trials have measured. Above 400 mg of magnesium in a day, diarrhoea is likely; above 25 mg of zinc a day for months, copper absorption falls, which the NHS links to anaemia and weakening of the bones.1
Sources
- NHS. Vitamins and minerals: others, including zinc and magnesium. nhs.uk.
- Lönnerdal B. Dietary factors influencing zinc absorption. Journal of Nutrition, 2000. PubMed 10801947.
- Samman S, Roberts DC. The effect of zinc supplements on plasma zinc and copper levels and the reported symptoms in healthy volunteers. Medical Journal of Australia, 1987. PubMed 3547053.
- Department of Health and Social Care. Great Britain nutrition and health claims (NHC) register. gov.uk.
- Jazinaki MS, Gheflati A, Moghadam MRSF, et al. Effects of zinc supplementation on sleep quality in humans: a systematic review of randomized controlled trials. Health Science Reports, 2024. PubMed 39377022.
- Rondanelli M, Opizzi A, Monteferrario F, et al. The effect of melatonin, magnesium, and zinc on primary insomnia in long-term care facility residents in Italy: a double-blind, placebo-controlled clinical trial. Journal of the American Geriatrics Society, 2011. PubMed 21226679.
- NHS. About melatonin. nhs.uk.
- Mah J, Pitre T. Oral magnesium supplementation for insomnia in older adults: a systematic review and meta-analysis. BMC Complementary Medicine and Therapies, 2021. PubMed 33865376.
- Wilborn CD, Kerksick CM, Campbell BI, et al. Effects of zinc magnesium aspartate (ZMA) supplementation on training adaptations and markers of anabolism and catabolism. Journal of the International Society of Sports Nutrition, 2004. PubMed 18500945.
- Sandström B, Arvidsson B, Cederblad A, Björn-Rasmussen E. Zinc absorption from composite meals. I. The significance of wheat extraction rate, zinc, calcium, and protein content in meals based on bread. American Journal of Clinical Nutrition, 1980. PubMed 7361691.
- NHS. Vitamin D. nhs.uk.
- Public Health England. McCance and Widdowson's Composition of Foods Integrated Dataset (CoFID), 2021. gov.uk.
This article is general information, not medical advice. Anyone on regular medicines or with kidney disease should ask a pharmacist or GP before adding either mineral.
