Probiotic Skin Care Is a Lie

If you’re reading this, I owe you an apology. About six years ago, there was a sudden rise in the number of products that claimed to optimize the skin’s microbiome, the collection of microorganisms living on its surface. The formulas contained probiotics, or live microorganisms derived from fermented foods or dirt, for example. 

But no matter the source, the storyline was the same: These probiotics were said to rebalance your skin’s microbiome by adding “good” bacteria that then (by a somewhat acrobatic leap of logic) could edge out the alleged “bad” bacteria and, in turn, among other things, reduce inflammation — thus bestowing you with happier, healthier skin. 

Parts of that story hold true, but if you string them together with a daisy chain of Boolean logic (if this, then that), probiotic-laced skin care ends up wearing a halo of scientific truth. But like all halos, it’s not real. That’s the mistake I (and many other editors) made when reporting on this phenomena in the mid-teens.

What We Know About the Skin’s Microbiome

What we knew then: There was — and is — plenty of research linking microbiome imbalances in the skin and gut to inflammatory skin conditions such as acne, rosacea, and eczema (there have been ample papers published in journals such as Clinics in Dermatology, the Journal of Investigative Dermatology, and the Journal of the American Academy of Dermatology). There are also plenty of people who have taken probiotic-infused skin-care products for a test drive and swear up and down that they work.

What I know now: On a video call with scientist Larry Weiss, the now-unaffiliated founding chief medical officer of one of those mid-teens, probiotic-based brands, something caught my attention. He said we can’t claim to “recolonize” the facial microbiome with skin care, even if it contains promising probiotics. Skin care with certain probiotics can potentially affect (and possibly benefit) our skin until it is washed away or those live microorganisms die, but it’s not fundamentally changing the microbiotic landscape on our skin, as I had reported. 

Do Probiotics Have Any Benefits for Skin?

So now, as a new wave of probiotic skin-care crests, I come from the past to set the record straight. There’s a laundry list of issues with putting faith in probiotic skin care (and “issues” is a nice word for it). Even the world’s foremost microbiome researchers can’t say for certain which specific strains of probiotics will have a lasting — or even short-term — effect on the skin, or how much of them we need to see a difference. “The science right now has revealed promising leads, but nothing particularly solid,” says Tami Lieberman, an assistant professor at MIT’s Institute for Medical Engineering and Science, who researches the principles governing colonization and personalization in the human microbiome.