Does magnesium cream actually work?

A magnesium cream is a magnesium salt — usually magnesium chloride — suspended in an emollient base of oils, butters and water. It is a cosmetic product, sold and regulated as skincare rather than as a medicine.

That is worth stating plainly, because magnesium is best known as a supplement, and a jar of cream sitting next to a bottle of tablets invites the assumption that they do the same job in a different format. They do not.

Magnesium's role in the body is not in question. It is an essential mineral involved in hundreds of processes, including the ones that let muscles contract and then release. People who are genuinely low in magnesium and correct that — through diet or oral supplementation — often notice a difference in muscle comfort and sleep.

What is much less settled is transdermal absorption: how much magnesium gets through intact skin, how deep it goes, and whether it reaches the bloodstream in a meaningful amount. The studies that exist are small, and reviewers who have looked at them tend to conclude that the evidence is suggestive rather than convincing.

Anyone telling you topical magnesium is a proven substitute for oral magnesium is ahead of the research. Anyone telling you it does nothing at all is ignoring how consistently people report that it helps.

Three things happen when you use a magnesium cream, and only one of them depends on absorption.

• The massage. Working a cream into a tight shoulder or a tired calf is itself effective — it increases local blood flow and it is the reason a five-minute application feels better than a five-second one.
• The cooling. Most magnesium creams, including ours, carry menthol. That sensation arrives within seconds and has nothing to do with the mineral.
• The ritual. Doing the same unhurried thing at the same time each evening is a genuine signal to the body that the day is closing.

None of that is a trick. It is simply a more accurate description of where the benefit comes from than "magnesium absorbs through your skin".

Give it a fair trial. Apply a generous amount — at least a quarter-sized scoop for a large area — to the same place at the same time daily for two to three weeks, and pay attention to how that area feels the following morning rather than in the first five minutes.

If the honest answer after three weeks is that it makes your evening more pleasant and your skin softer but nothing more, that is a perfectly good reason to keep using it, and a perfectly good reason to stop.

A wellness ritual, not a medical treatment. For external use only. If you have persistent pain, numbness or a medical condition, talk to a doctor or pharmacist — a cosmetic is not the right tool for that.