What Is Cetearyl Alcohol? We Decode This Misunderstood Ingredient

Understandably, this can feel like a personal stab to your skin care-loving heart. Don't be so quick to toss that product, though. Cetearyl alcohol is a commonly misunderstood ingredient—and it's not as bad as you might think. 

Chemically speaking, cetearyl alcohol is a fatty alcohol. It's made of cetyl alcohol and stearyl alcohol, two fatty alcohols also used in skin care. On ingredient labels, cetearyl alcohol is sometimes listed as cetostearyl alcohol, cetyl/stearyl alcohol, or C16-18 alcohol.

So, about that "alcohol-free" label. According to the Food and Drug Administration (FDA)1, "alcohol-free" refers to the lack of ethyl alcohol—not alcohol in general. Fatty alcohols (like cetearyl alcohol) are fair game. 

On skin care labels, cetearyl alcohol is often listed as an "inactive ingredient." That's because it usually doesn't help a product's therapeutic effects on the skin. Instead, it's used to enhance the formulation of a product. Here's how:

According to Frey, most skin care products on the market are made of water and oily ingredients. (These oily ingredients function as emollients, fragrances, and other purposes.) Cetearyl alcohol stops the water and oils from separating, which maintains the composition of the product.

To be effective, a product should have a consistent formula. Otherwise, the active ingredients will spread unevenly—which defeats the purpose of using product to begin with. Cetearyl alcohol prevents this by keeping the ingredients together, like a neat and tidy package.

Due to its oily consistency, cetearyl alcohol creates "a smoother, creamier texture to make products more cosmetically appealing," says Ciraldo. Think velvety, hydrating moisturizers and luscious foaming cleansers. Its thickening action also makes it easier to spread on the skin, further enhancing even application. (After all, there's nothing more disappointing than trying to work with a runny, watery formula.) 

Cetearyl alcohol is also an emollient, which means it can make the skin look and feel softer, says Frey. It works by filling in cracks and uneven surfaces—the culprits behind dry skin. Even then, cetearyl alcohol isn't used in skin care products for this reason. It's kind of like an extra perk that proves just how diverse alcohols can be.

 Yet, it is possible to have an allergic reaction. This risk in higher in people who have eczema, as they have a compromised skin barrier, and who often use multiple topical medicines. In fact, an article from the 1980s2 states that about 1% of people with eczema are allergic to cetyl alcohol, stearyl alcohol, or a mixture of both—cetearyl alcohol. A 2007 article also reported five cases of allergic contact dermatitis due to cetearyl alcohol. 

Cetearyl alcohol allergies are extremely rare, though. If you develop irritation or swelling after using a product with cetearyl alcohol, consider if it was caused by another ingredient. When in doubt, talk to your dermatologist.