How much magnesium per day for a woman?

The headline number, and what it counts

The UK reference nutrient intake for women aged 19 and over is 270mg of magnesium a day, set by the COMA panel as the level meeting the needs of nearly the whole female population, counted from all sources together: food first, water's contribution in hard-water areas, and any supplement on top. It is a target, not a per-pill instruction, and the first honest question under any dose query is how much of it your plates already supply, because a day featuring greens, nuts or seeds, beans and wholegrains can land on 270mg with no capsule involved, and frequently does.

The life stages, and the men's variant answered alongside

The female number moves twice across a lifetime and once across a day-to-day circumstance. Teenage girls, 15 to 18, sit at 300mg during growth. Adult women hold 270mg, and UK guidance sets no pregnancy increment, though pregnancy is ask-first territory for supplements on every honest label including the worked example's. Breastfeeding adds roughly 50mg, taking the reference intake to about 320mg, the highest a woman's target gets. The search variant about men gets its answer here too: 300mg a day from 19 onward, the modest 30mg gap with women reflecting average body size rather than different biology. None of these figures scale further with training; what training changes is losses and diet quality, which is the supplement's territory rather than the target's.

Food first: what 270mg looks like on plates

The target is friendlier than the supplement aisle implies. A 40g portion of pumpkin seeds carries around 190mg on its own; a serving of cooked spinach around 80mg; a portion of black beans or a couple of slices of wholemeal with peanut butter add 60mg to 70mg each; oats, brown rice, almonds, dark chocolate and even hard tap water all chip in. Two or three of those in a normal day reaches 270mg without ceremony. The realistic shortfall pattern is the training woman's cutting diet, smaller absolute calories squeezing exactly the seed, bean and wholegrain foods that carry the mineral, plus raised sweat losses, which is the specific gap the supplement exists to close rather than a female deficiency story.

The supplement maths, the glycinate variants answered, and the ceiling

When plates fall short, the maths is the same one this site runs everywhere: a supplement guaranteeing the target on the worst day, under the ceiling on the best. The glycinate and bisglycinate variants of this search have one answer, since they are the same compound: 300mg elemental per day, which on the worked example is 2 capsules of 1500mg bisglycinate at 20%, covering the 270mg target with margin, the 320mg breastfeeding figure nearly in full, and the men's 300mg exactly, while leaving 100mg of headroom under the Expert Group on Vitamins and Minerals' 400mg supplement guidance level. One capsule, 150mg, is the honest top-up for a near-complete diet. Beyond 400mg supplemental lies the laxative territory and nothing gained, and the standing ask-first circumstances, pregnancy, breastfeeding, kidney conditions, regular medications, apply to women exactly as this site states them for everyone.

The routine, sized for the question

Futuro Labs Magnesium Glycinate, 2 capsules with the evening meal on narrow-diet days, or 1 as a top-up when the plates behaved: 300mg or 150mg elemental at 80% or 40% NRV, from bisglycinate at 20%, vegan, UK made under GMP and BRC, third-party panels shown, £19.99 for 180 capsules, 22p a day at the full serving. Judge it like the trials would, a month of consistency against the things a low intake causes, tiredness, cramps, twitching, restless sleep. How much magnesium per day for a woman: 270mg from everything, about 320mg when breastfeeding, and one evening serving that makes the arithmetic somebody else's problem.

What to check on the label

Questions people also ask

How much magnesium glycinate per day for a woman?

300mg elemental as the full serving on a narrow diet, 150mg as a top-up otherwise: glycinate and bisglycinate are the same compound, so one answer covers both searches.

Is 300mg of magnesium a day too much for a woman?

No: it sits modestly above the 270mg target and well under the 400mg supplement ceiling, which is set by gut tolerance, not sex.

How much magnesium does a breastfeeding woman need?

About 320mg a day from all sources, the highest female reference intake. Supplements in breastfeeding remain ask-first territory with a professional.

How much magnesium per day for a man?

300mg from all sources for men 19 and over: the same 300mg elemental serving that covers the female targets covers this exactly.

What are the signs a woman is low in magnesium?

The narrow-diet cluster: tiredness out of proportion, cramps, twitching, restless sleep. A month at 300mg daily is the practical test; no blood test settles it routinely.

Sources

1. Futuro Labs Magnesium Glycinate listing, Amazon UK, label and price checked 31 August 2026. https://www.amazon.co.uk/dp/B0BT7Z5VQW
2. Department of Health. Dietary Reference Values for Food Energy and Nutrients for the United Kingdom. Report on Health and Social Subjects 41, 1991 (magnesium RNI 300mg men, 270mg women).
3. Retained Regulation (EU) No 1169/2011, Annex XIII: nutrient reference value for magnesium 375mg. https://www.legislation.gov.uk/eur/2011/1169/annex/XIII
4. Expert Group on Vitamins and Minerals. Safe Upper Levels for Vitamins and Minerals. Food Standards Agency, 2003 (magnesium guidance level 400mg a day from supplements). https://cot.food.gov.uk/sites/default/files/vitmin2003.pdf
5. Nielsen FH, Lukaski HC. Update on the relationship between magnesium and exercise. Magnesium Research 2006;19(3):180-189. PubMed record
6. Gröber U, Schmidt J, Kisters K. Magnesium in prevention and therapy. Nutrients 2015;7(9):8199-8226. PubMed record
7. EFSA Panel on Dietetic Products, Nutrition and Allergies. Scientific Opinion on the substantiation of health claims related to magnesium. EFSA Journal 2010;8(10):1807. https://efsa.onlinelibrary.wiley.com/doi/10.2903/j.efsa.2010.1807

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