Here’s Why Dermatologists Are Excited About Fermented Skin Care

From slugging to squalane, we love a skin care trend that actually delivers. That’s one reason why we’ve turned our attention to fermented skin care products. If you have images of sauerkraut- and kimchi-infused serums dancing through your mind, these products aren’t quite so literal—but they do rely on the same process that blesses us with those tasty fermented foods. So, we set out to learn more about the fermentation process behind these products, what sets them apart from other treatments on the market, and whether they’re worth a try if you’re thinking about shaking up your skin care routine.

What is fermented skin care, anyway?

Lately, you’ll see skin care products with all sorts of fermented ingredients on the label, including soy, kelp, rice water, various botanicals, and even active ingredients we know and love like vitamin C, hyaluronic acid, and more.

When it comes to making fermented skin care ingredients, we have good ol’ bacteria to thank, board-certified dermatologist Marisa Garshick, MD, FAAD, tells SELF. Essentially, fermented ingredients have been exposed to microorganisms. These beneficial bugs break down the ingredients into smaller molecules, Dr. Garshick explains. The smaller the molecule size is, the easier it is for an ingredient to penetrate the skin more deeply, she says.

It’s not far off from what happens when yeast is added to grapes to produce wine, board-certified dermatologist Azadeh Shirazi, MD, tells SELF. Using fermentation in skin care may also help “enhance [the] potency” of certain ingredients, she says, which, in theory, should lead to better results.

What are the benefits of using products with fermented ingredients?

It all comes back to that smaller molecule size, Dr. Garshick says. She explains that your skin barrier is protective by design, so ingredients that can be absorbed more easily stand a better chance of having substantial effects. For example, hyaluronic acid—a beloved humectant that helps draw water to the surface of the skin—is a fairly large molecule, which makes it harder for the skin to absorb. When hyaluronic acid is fermented, it can sink deeper into the skin and work its hydrating magic more thoroughly, Dr. Garshick says. In other words, it’s possible that fermenting ingredients that we already know to be helpful in addressing common concerns like dryness, acne, dullness, and fine lines, may increase their capacity to deliver the results you want. On the flipside, because products containing fermented ingredients tend to be more potent, they could potentially cause a reaction in sensitive skin (similar to chemical exfoliants), so they should be used with some caution. If they’re more potent, they could be more irritating.

Despite its promise (and derms’ interest in it) as a trend, fermented skin care is a fairly new concept, so there isn’t a ton of specific research on it at the moment. That makes the full breadth of its effects (and possible benefits) a bit murky. Dr. Garschick points to a couple of small studies (one on animals and one on humans) that suggest certain fermented ingredients, including red ginseng and a barley and soybean formula, showed some potential in boosting skin hydration and fighting signs of aging, but they’re far from conclusive. Larger studies on diverse groups of people need to be done to better understand the possibilities of these ingredients. Ultimately, Dr. Garshick says we still have more to learn about this trend (and the skin’s microbiome in general).

This is a valuable reminder to take claims around any emerging beauty trend with a grain of salt. As Dr. Shirazi puts it: “There are potential benefits, but there’s not a lot of research on their effectiveness. So I don’t consider it the holy grail of skin care just yet.”

Who should try fermented skin care products?

“While further research is needed, fermented ingredients are thought to be safe, so if someone is interested, it is reasonable to try,” Dr. Garshick says. Just make sure to note the ingredients before you apply them and avoid any known irritants; a patch test is never a bad idea, especially if you’re trying a product that has multiple active ingredients in it. Apply a dime-sized amount of the product on the inside of your elbow or on your neck and check on it a day later. If you don’t see any irritation or feel itchy, you’re probably good to go.

Now that you’re a bit more familiar with fermentation skin care, here are some stand-out products that employ the process to potentially boost the effects of hydration, exfoliation, brightening, and more.