Some skincare ingredients are more obscure than others (phenoxyethanol, anyone?) but even the ones that sound familiar, like colloidal oatmeal, can be shrouded in mystery. Sure, we all know what oats are and if you're one of the many with dry, itchy, eczema-prone skin, you might even use colloidal oatmeal on a daily basis. But if we asked you to list all of its skin benefits and possible side effects, could you? In the name of getting more acquainted with the many ingredients we slather on our skin each day, we reached out to board-certified dermatologists for the lowdown on the skincare ingredient.
Meet the Expert
- Hadley King, MD, is a board-certified dermatologist based in New York.
- Nava Greenfield, MD, is a board-certified dermatologist with Schweiger Dermatology Group in New York.
Keep scrolling to find out everything there is to know about colloidal oatmeal in your skincare products.
Colloidal Oatmeal
Type of ingredient: Skin protectant.
Main benefits: Protects, prevents water loss, and soothes the skin.
How often can you use it: The recommended use for colloidal oatmeal is twice daily.
Works well with: Colloidal oatmeal can be used in conjunction with ingredients that can be irritating to the skin, such as alpha- and beta-hydroxy acids and retinoids, to help minimize irritation and disruption of the skin barrier.
Don't use with: Colloidal oatmeal works well with most, if not all, other ingredients.
What Is Colloidal Oatmeal?
According to Greenfield, colloidal oatmeal is ground oatmeal, which is then placed in a liquid medium for better application and absorption into the skin. Studies show that colloidal oatmeal can function as a cleanser, moisturizer, skin soother, and protective anti-inflammatory agent. The skin protectant is available in various forms (such as powders, gels, and creams) and is found in bath and shower products, shampoos, cleansers, ointments, and moisturizers.
Benefits of Colloidal Oatmeal for Skin
As described by King, oatmeal is a classic ingredient that is commonly used as a soothing agent to relieve itchy skin and soothe irritation caused by dry skin conditions, but it also has a variety of functions. Discover the many benefits of colloidal oatmeal in skincare below.
- Protects: "One of the most important functions of the skin is to provide a barrier between the body and the environment," Greenfield says. "There are many cases where the skin is not performing this function optimally. Some examples are if there is a genetic predisposition to eczema, or the skin is very dry from weather or washing away its natural emollients and protectants. This is where colloidal oatmeal comes in." Clinical studies have shown colloidal oatmeal helps to strengthen the skin’s protective barrier.
- Prevents transepidermal water loss (TEWL): According to Greenfield, colloidal oatmeal works by creating a film on top of the skin's surface. After using colloidal oatmeal in studies, both the amount of water in the skin that was lost and overall skin hydration showed improvement. King adds that colloidal oatmeal contains high concentrations of starches, which contribute to its water-binding properties.
- Soothes irritation: According to King, the cellulose and fiber in colloidal oatmeal give it emollient properties that calm redness and irritation. Greenfield adds that it's great for patients with mild-to-moderate eczema or ichthyosis as well as those with itchy skin and sunburns.
- Has anti-inflammatory properties: Thanks to the phenols it contains, colloidal oatmeal also shows antioxidant and anti-inflammatory activity, King says.
- Absorbs UV: Studies show the phenols in the colloidal oatmeal also may help with absorbing UV radiation.
- Cleanses: According to King, colloidal oatmeal contains saponins, which have cleansing properties; she adds that it also has anti-fungal properties, thanks to the avenacins.
- Non-irritating: For the most part, colloidal oatmeal is non-irritating and safe for use with all skin types.
- Available over-the-counter: Unlike some super skincare ingredients, colloidal oatmeal products are available in most beauty and drugstores.
Who Should Use It
In general, colloidal oatmeal can be used by anyone to hydrate and moisturize the skin, but King says it is particularly helpful for those with dry skin and conditions like eczema.
Side Effects of Colloidal Oatmeal
According to King, generally, side effects of colloidal oatmeal are uncommon, but burning, stinging, redness, or irritation are possible and the symptoms can range from mild to severe. "Oat allergies are not common but can occur," King says. "This might result in blotchy, irritated, and itchy skin."
Greenfield adds that there is always a possibility that the skin could react poorly to a new exposure, but the source of the reaction could be harder to determine. "Although some of these concerns are valid, be careful to check the ingredients of the product because your skin may actually be reacting to a preservative in the product, which is common, and not the colloidal oatmeal," she says. "So sometimes you need to tease out what part of the product is causing the reaction, and it may not be very obvious."
To test out how your skin might respond to a product, Greenfield recommends conducting a patch test on the inside of your forearm. "Apply a small amount of the product in that location twice daily for five days," she explains. "If no reaction occurs, it's probably a safe bet that the rest of your skin will tolerate it." In general, she suggests avoiding use if you have contact allergies to multiple allergens and recommends switching to a product that is hypoallergenic instead.
How to Use It
As previously mentioned, colloidal oatmeal is used in an assortment of skincare products, so the use of it depends on each individual product. One thing to note, however, is that the medium the colloidal oatmeal is placed in will aid in its effectiveness, according to Greenfield. For topical moisturizers, she recommends sticking with thicker, heavier formulas rather than thinner lotions, which have more water content and fewer oils. Greenfield also suggests using it as an additive to your bath to help prevent the water from drying out your skin. And to increase its healing and protective functions, Greenfield suggests combining it with medicinal honey before application.
King generally recommends using a moisturizer containing colloidal oatmeal at least twice per day, including immediately after a bath or shower and before bed. She adds that moisturizers containing colloidal oatmeal can be used as often as you would like, but Greenfield suggests limiting your use to twice daily. "If you need to apply more than twice daily, I would recommend alternating with a different type of emollient," she says.