Anyone who’s picked up a magazine or visited a health food store recently should know that probiotics—a certain type of “good” bacteria—can aid your digestive health. But lest you dismiss these little microorganisms as just another vaguely-beneficial health supplement, know this: they’re actually quite the overachievers. And unlike your high school class president, you’ll actually want to hear about all that they can do—especially if you suffer from acne, eczema, or rosacea.

We spoke with Dr. Roshini Raj— gastroenterologist, doctor of internal medicine, and founder of the probiotic-based skincare line, TULA —and asked her to school us on all the skin benefits of probiotics (including why we should consider smearing it on our faces).

Bacteria Vs. Your Skin

First things first—let’s establish the fact that bacteria already exists on your skin. If that was a bombshell, we apologize. Here’s the good news: most of the bacterial cells that live inside and on your body are harmless, according to the American Academy of Dermatology. In fact, some studies show that they can even be beneficial. But as any acne or rosacea-sufferer knows, it’s not all sunshine and roses—sometimes, your body may think living microorganisms are a potential threat, and spring into action to counter it, resulting in inflammation, redness, bumpiness, and more. This is where probiotics come in.

Topical Probiotics: Protect

According to the American Academy of Dermatology, topical probiotics work via “bacterial interference”—they literally interfere with the ability of bad bacteria to provoke an immune reaction, by preventing your skin cells from seeing them in the first place.

Topical Probiotics: Calm

“Recent research suggests that when applied topically, probiotics secrete anti-bacterial and anti-inflammatory substances that help with conditions like acne, eczema and rosacea,” Dr. Raj says. “By calming inflammation, probiotics are also effective in targeting wrinkles and preventing premature aging.” […]