For decades, the pursuit of beauty has involved anepic battle against the microorganisms on our skin. Dull complexion? Scrub away the dirt (and the little critters living therein) with antibacterial soap. Shiny T-zone? Strip off the oil (and the bugs that thrive on it) with antiseptic cleansers and toners. But now, beauty chemists are trying a reversal of tactics. Instead of anti, they’re embracing pro—probiotic, to be precise. Rather than eviscerating all bacteria, they’re singling out the beneficial varieties and figuring out how to harness their power.
If you hear the word “probiotic” and think of Jamie Lee Curtis hawking yogurt, you’re not too far-off. Probiotic products, whether ingestible or topical, contain bacteria friendly to our digestive systems. Yogurt, pickles, kombucha, sauerkraut, and other fermented foods naturally contain probiotics—live strains that are able to sail through the acidic stomach environment and enter the gut, where they proliferate. Their presence can kill harmful bacteria, enhance the immune system, and strengthen the intestinal lining.
So what does this have to do with skin? A lot, it turns out. “There’s convincing evidence now that bacteria in your gut interact with your immune system to produce changes in your skin,” says Whitney Bowe, a New York dermatologist who has written extensively on the topic. Harmful bacteria, she explains, injure the stomach lining, making it more permeable. This not only allows irritating substances to float into the bloodstream instead of being excreted, but it also sets off alarm bells in the immune system.As a result, inflammatory chemicals—causing sensitivity, redness, and itching—get released throughout the body, including the skin, says Raphael Kellman, a holistically focused internist and the author of The Microbiome Diet.
It makes sense then that people who eat or drink probiotics regularly to enhance their insides often start looking better on the outside too. “You can tell longtime kombucha drinkers by their clear skin,” swears Daina Trout, a nutritionist who loves the tingly-tasting fermented drink so much, she now sells her own brand, called Health-Ade.
The evidence is more than just anecdotal. In a 2013 paper by the Massachusetts Institute of Technology titled “Probiotic Bacteria Induce a ‘Glow of Health,’” the authors noticed that female mice had shinier fur and thicker skin within seven days of eating yogurt. They theorized that probiotics somehow prolonged thegrowth phase of the hair and influenced the immune system.
Needless to say, today probiotics are an active area of research for beauty brands as well as for supplement manufacturers. In 2014, L’Oréal researchers published a paper reporting that an ingested form of lactobacillus paracasei improved skin sensitivity in patients by, among other things, reducing water loss from the skin’s surface. An earlier study found that the same strain, when ingested, tamed dandruff. Hum, a company with the motto “Beauty starts from within,” labels its probiotic-packed Gut Instinct capsules “friendly bacteria that benefit your skin, health, and beauty.” Sonya Dakar promotes its Acidophilus Flora supplement with a list of benefits that include “healthy skin” and “optimal digestion.”
But billions of bacteria also live directly on the epidermis, and, according to Julie Segre, a geneticist and skin biologist who is decoding the genome of skin bacteria at the National Institutes of Health, the habits of those bugs affect the way our skin looks, feels, and even smells. Certain inflammatory skin disorders, she says, have been associated with an imbalance of these bacteria, and the chemicals they produce can shift the workings of the immune system. For instance, P. acnes, the bacteria that causes acne, is genetically coded to rough up the lining of your pores or stick to and block them, which can ultimately lead to pimples. Staphylococcus aureus (known as “staph”) appears to release a toxic chemical that signals the immune system to produce granules that cause eczema, says Gabriel Nuñez, a professor of pathology at the University of Michigan, who wrote about his finding in a recent issue of Nature.
As in the gut, the rogue strains on top of the skin can be halted or slowed when overwhelmed with legions of friendly bacteria. These microbial aid workers—which, researchers suspect, include the lactobacillus and bifidus strains—“actually keep skin cells from detecting the presence of the bad bacteria and prevent an inflammatory response,” Bowe says. They also assist in all sorts of skin-enhancing activities, such as building collagen, strengthening the protective barrier, and retaining moisture. She advises patients with conditions like eczema, rosacea, and acne to eat probiotic-heavy foods and apply a mask weekly made with that old health-food-store recipe: full-fat yogurt and honey. “Many say they see improvements within a matter of weeks,” says Bowe, who is also a clinical assistant professor of dermatology at the Icahn School of Medicine at Mount Sinai Medical Center, in New York.
Unlike Bowe’s yogurt mask, many off-the-shelf topical varieties, including the gastroenterologist-created, probiotic-focused Tula line, contain ferments—secretions from beneficial bacteria—rather than the bacteria themselves. Sunlight, pollution, and chemicals from other beauty products would make it difficult for the microscopic organisms to survive on the skin, explains Lili Fan, an ophthalmologist who is also a biochemist for beauty brands and the creator of a line of probiotic topicals. “The ferments are easier to control and easier to deliver into the skin,” she says.
Studies on topical agents to treat patients suffering from acne and eczema suggest that we could be seeing a lot more of these products. A news release by the American Academy of Dermatology called “Could Probiotics Be the Next Big Thing in Acne and Rosacea Treatments?” points out that the ferments themselves have antimicrobial properties. “They can create holes in bad bacteria and kill them,” it noted.
And beauty companies are currently exploring how much further they can take these topical ferments. In the case of Estée Lauder’s Micro Essence Skin Activating Treatment Lotion, which debuted last July, the extracts of bifidus contain “signaling molecules” that tell the skin cells to do things like produce collagen, says Nadine Pernodet, Ph.D., Estée Lauder’s vice president of skin biology and bioactives. The brand is collaborating with researchers at universities around the globe to find new extracts for future formulations.
The other advantage of ferments over live bacteria is that, simply put, they don’t stink. As Mike Bush, the vice president of Ganeden Biotech, a supplier of probiotics to the food and beauty industries, explains, the medium in which good bacteria strains thrive has “a very distinctive, malty scent.” Still, some companies are betting that the skin-obsessed will brave a little smelliness, a bit of inconvenience, or both, if the result is a radiant complexion. Dairyface’s probiotic Beauty Mooscow Hand and Body moisturizer, for instance, has live cultures, which means it requires refrigeration and has a shelf life of six months. And the Beauty Chef, an Australian brand known for its probiotic nutritional powders, is launching a skin refiner in October that, aroma-wise, is really only appropriate for use in the privacy of one’s bathroom. “I was hesitant because of the smell,” admits Carla Oates, the company’s founder. “But early testers were so happy with the results, they said they didn’t mind and begged us to launch it.”
Her customers aren’t the first to hold their noses in the name of beauty. Cleopatra kept her skin smooth and supple by sitting in a milk bath, which sounds pleasant enough. But the pharaoh femme fatale had a trick to make her soaks extra effective: She let the milk sit out in the sweltering Egyptian air for three bacteria-boosting days before taking the plunge.