Dermatologists Agree: This Is The One Super-Dehydrating Skincare Product Ingredient You Have To Stop Buying

How Products With Isopropyl Alcohol Dehydrate Aging Skin 

Aging or mature skin is often characterized as dry and fragile, Ranglani says. She notes that “when shopping for skincare items, those with this skin type should avoid using products that contain simple alcohols.”

Simple alcohols are ingredients in skincare commonly used as solvents and are notoriously dehydrating because they evaporate very quickly. “When applied topically, simple alcohols draw out moisture from the skin while stripping it of its protective barrier,” Ranglani adds. “When left with no moisture or protection, skin aging is accelerated, and the skin is more vulnerable to environmental damage.” 

So, what constitutes simple alcohols? Ranglani says to beware of the following types: alcohol denat (denatured alcohol), SD alcohol 40 (specially denatured alcohol), Ethanol and—most importantly— isopropyl alcohol. 

Alcohol dehydrates the skin, making it more sensitive and killing the barrier function. Consequently, as Sobchak explains, “the skin turns red, increasing sensitivity, and may develop eczema.” She says to check out for labels “containing isopropyl alcohol and avoid them completely.” 

Isopropyl is one to watch out for due to its ultra-drying, flake-inducing abilities, adds Angers. “One skincare ingredient that can dry out aging skin is isopropyl alcohol is one example, commonly found in skincare products like over-the-counter toners,” she says. 

Angers explains that this popular over-the-counter toners or astringent ingredient is often used “because it helps other ingredients to be absorbed into the skin and allows for a smoother application.” (That is, if your skin is younger, contains more moisture, and isn’t dry already!)

Isopropyl alcohol, she says, can be drying to the skin if it's “in high concentration” and/or “combined with other drying ingredients” (such as sulfates). In these cases, it is especially drying to aging skin as, she notes, “aging skin is already battling transepidermal water loss” (the skin's inability to retain moisture).

Angers concludes that a good rule of thumb when reading product ingredients is that “if it is one of the first ingredients listed, it is in higher concentration than ingredients listed further down.” Good to know!