While we’ve been programmed to pre-cleanse, cleanse, and exfoliate, it turns out that the dirty secret to great skin is bacteria. That’s right, research shows clean skin still has trillions of microbes on it, and these bugs play a major role in our skin’s health. “Our skin is covered with trillions of microorganisms you can’t see, primarily bacteria, that are essential to healthy and beautiful skin,” says Whitney Bowe, MD, a dermatologist in New York City and author of The Beauty of Dirty Skin. “These microbial critters are part of your skin's health and behavior, and many of them provide vital functions for your skin that the human body actually can't perform on its own.”
Dr. Bowe explains that over-cleansing will not only strip away the skin’s natural oils, but it will also upset its sensitive microbial balance. “The bacteria on our skin exist in a very delicate equilibrium—a delicate balance or harmony even—that keeps our skin functioning at its optimal level,” she says. “When the bacterial balance is maintained, our skin is pumping out collagen, sealing in moisture with ceramides, and telling our immune systems to calm down. But when we upset that delicate balance by rubbing and scrubbing with loofahs, buff puffs, wash cloths, harsh soaps with a high pH, or antibacterial soaps with biome-sabotaging ingredients like triclosan, our skin begins to suffer.” This can lead to a number of skin issues, including eczema, acne, dry skin, and premature aging.
Healthy bacteria also acts as a protective shield. In fact, researchers recently found that Staphylococcus epidermidis produces a molecule called 6-N-hydroxyaminopurine (6-HAP) that may provide natural protection against skin cancer. “The presence of this strain may provide natural protection, or it might be used therapeutically to inhibit the growth of various forms of cancer,” Richard Gallo, a co-author of the study from the University of California, San Diego, writes in the journal Science Advances.
When the strain was introduced to mice with melanoma cells, the tumors were over 60 percent smaller than those that had not received the strain. “Not only did this substance appear to slow the growth of melanoma cells, but it also appeared to reduce the number of pre-cancers formed when mice were exposed to UV light,” says Dr. Bowe. “In my opinion, this science is truly groundbreaking, and represents a revolution in the field of skin care and dermatology. Scientists are turning towards probiotics to fight infections, fight chronic skin diseases such as acne and rosacea, and now even to fight cancer.”
To keep your bugs in check, steer clear of harsh, anti-bacterial soaps or cleansers with a high a pH. Instead, Dr. Bowe says to look for words like gentle, pH balanced, and hydrating. She recommends La Roche Posay Toleriane Cleanser ($15; ulta.com), which is formulated with prebiotic thermal spring water to help restore that healthy balance. Use only your fingertips when cleansing—no instruments or tools—and moisturize immediately after. “Moisture is critical to microbial growth on the skin, and moisturizers preserve the skin's physical barrier and maintain the normal composition of the microbiome,” she explains. “If your skin feels tight or dry after you cleanse, you are not respecting your microbiome.”