Can using magnesium topically help with sleep? Medical experts are skeptical
MICHEL MARTIN, HOST:
The idea of taking magnesium supplements for sleep has been around for a while. Health influencers are now encouraging people to use it as a lotion. One market research group estimated the market last year for topical magnesium was more than $400 million. As NPR's Katia Riddle reports, medical experts are skeptical.
KATIA RIDDLE, BYLINE: There are a lot of testimonials on TikTok about magnesium lotion.
(SOUNDBITE OF TIKTOK MONTAGE)
UNIDENTIFIED TIKTOKKER #1: Did you know rubbing magnesium cream on your child's feet can help with sleep?
UNIDENTIFIED TIKTOKKER #2: This kit with both a spray and a lotion. Very easy application.
UNIDENTIFIED TIKTOKKER #3: Y'all, this magnesium lotion and spray is magic in the bottle.
RIDDLE: Those are posts from the TikTok Accounts CottageCalderon, Wellover40ish and MadisonClecker (ph). Someone who's not a TikTok influencer - sleep specialist John Winkelman at Harvard. He says patients have told him they're using magnesium lotion for sleep.
JOHN WINKELMAN: Somebody told me about a magnesium butter. I was a little confused by that because I thought you'd put that on toast. But no, in fact, you rub it on your legs.
RIDDLE: There's a little research about the benefits of oral magnesium and even less around the use of topical magnesium for sleep or anything else. Winkelman is skeptical, but he says, in this case, his patient felt differently.
WINKELMAN: She did say that magnesium butter was helping.
RIDDLE: He says, in matters of sleep, placebos can be especially powerful. So if his patient thought it was helping, why not?
WINKELMAN: The risks of magnesium, applying it to your skin, are probably extremely small.
RIDDLE: That said, says Winkelman, he's not recommending it for patients anytime soon. For one thing, supplements are not regulated by the FDA, so it can be hard to know exactly what you're getting. It's also not a proven treatment for specific conditions. Restless leg syndrome is something that he treats frequently, for example, and something that influencers swear can be treated with magnesium lotion.
WINKELMAN: I really don't feel that it's fair to recommend things that I really don't think have been substantiated as effective.
RIDDLE: There are approved treatments for restless leg syndrome, including some taken orally, which doctors say is generally a much more efficient way to receive medication. Nicholas Theodosakis is a dermatologist at Harvard.
NICHOLAS THEODOSAKIS: The problem with this is the skin is a barrier, not a sponge.
RIDDLE: There are a few kinds of substances that are well suited to absorption through the skin, he says. There's no evidence that magnesium is one of those. Theodosakis says that the benefits of magnesium lotion are likely from its moisturizing components.
THEODOSAKIS: Anything that comes in like a cream base or an ointment base is just automatically going to be good for the skin.
RIDDLE: Theodosakis says as a dermatologist, he sees a lot of these kinds of trends. Skin, he says, is a popular target for health fads.
THEODOSAKIS: I think it's just, you know, the nature of skin. It's visible. It's highly linked to, you know, emotional well-being and psychology and culture. And you also just have quite a lot of it.
RIDDLE: He agrees magnesium lotion probably won't hurt you, except possibly, he says, in the pocketbook.
Katia Riddle, NPR News.
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