Which magnesium supplement is best for women in perimenopause?

There is no proven best magnesium for perimenopause. Most women can get the 270 mg a day they need from food. If you supplement, keep to 400 mg a day or less from supplements, read the label for elemental magnesium, and know that oxide was absorbed less well than other forms in a direct comparison.

• UK guidance puts women's need at 270 mg a day, from foods such as spinach, nuts and wholemeal bread. There is no separate figure for perimenopause.
• Taking 400 mg a day or less from supplements is unlikely to cause harm. Too much magnesium from supplements can cause diarrhoea.
• In a direct comparison, magnesium oxide was absorbed far less well than the chloride, lactate and aspartate forms, which were similar to each other. Glycinate was not tested.

The number

Women aged 19 to 64 need 270 mg of magnesium a day [1]. Spinach, nuts and wholemeal bread are good sources, and a varied diet usually provides most or all of it. There is no separate UK figure for women in perimenopause.

If you take a supplement, the guidance is that 400 mg a day or less from supplements is unlikely to cause any harm, and that too much can cause diarrhoea [1]. That figure is a safety level, not a target, and it is separate from the 270 mg you need from all sources.

What magnesium is authorised to say it does

Magnesium carries several GB-authorised health claims. Among them: magnesium contributes to normal psychological function, to a reduction of tiredness and fatigue, to normal muscle function, and to the maintenance of normal bones [2]. A product may carry these when it supplies enough magnesium to meet the conditions set out in the register.

They describe magnesium doing its ordinary job at any age. None of them is a claim about perimenopause, and a food supplement may not claim to act on a medical condition.

Which form

Magnesium supplements come as different compounds: oxide, citrate, glycinate (often sold as bisglycinate), chloride, malate and others. The compound affects how much is absorbed and how much space the magnesium takes up in a capsule.

The clearest direct comparison measured absorption of four forms in healthy adults. Magnesium oxide was absorbed poorly, about 4 per cent. Magnesium chloride, lactate and aspartate were absorbed significantly better, and about equally well as each other [3]. The study did not test glycinate or citrate, so it cannot rank them, and it was small. It measured absorption, not any effect people would notice, and it does not identify a best supplement for perimenopause. What it does show is that oxide delivers less magnesium for the same amount swallowed.

Reading the label

Labels give either the weight of the whole compound or the weight of the magnesium in it, often called elemental magnesium. Only the elemental figure counts towards the 270 mg a day. A capsule labelled with a large compound weight may contain much less magnesium, because most of the weight of glycinate or citrate is not magnesium. Look for the elemental amount per serving and add it to what you get from food before deciding on a dose.

Who should check first

Magnesium can reduce how well some medicines are absorbed when taken at the same time, including some antibiotics and some medicines for bone. If you take regular medicines, or have kidney disease, ask a pharmacist before starting a supplement and how far apart to take them.

Where this leaves you

Start with food. If you choose a supplement, check the elemental amount, bear in mind that oxide was the least well absorbed form in the one direct comparison, and stay at or below 400 mg a day from supplements. If you are buying magnesium for a specific symptom, a GP is a better first stop than a supplement aisle, because tiredness and muscle symptoms in midlife have several possible causes.

Published by: Suggestic Inc, herstack.co.uk. The HerStack editors. 2026-10-02. This page has not been reviewed by a clinician.