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Meet your makeup and skincare routine’s longtime BFF: isododecane. Never heard of it? Then listen up, because it’s an ingredient that’s in practically every beauty product you use. From moisturizers and foundations to lipsticks, eyeliners, and mascaras, isododecane is a staple in the cosmetic world, and it’s time you learned more about it.
Okay, it’s time to get a bit more detailed. What is isododecane, exactly? In simple terms, it’s an emollient and a solvent, which means that it helps your skin stay hydrated by locking in moisture at its surface, while also being a delivery mechanism for pigments and silicones in makeup. This makes it a great inclusion for skincare and cosmetic beauty products. Here’s the thought process—the more hydrated and even-surfaced your skin is, the longer the products stay on throughout your day. If you’re still a little confused, we feel you. That’s why we consulted board-certified dermatologists for extra help.
Meet the Expert
- Purvisha Patel, MD, is a dermatologist and the founder of Visha Skincare.
- Stacy Chimento, MD, is a dermatologist with Riverchase Dermatology.
Keep reading to find out the benefits (and concerns) of using isododecane in your routine. Your skin will thank you.
Isododecane
Type of Ingredient: Emollient and solvent.
Main Benefits: It acts as a moisture-locking barrier for the skin, keeping it hydrated and smooth. In addition to this (and while not a skincare benefit), isododecane contributes to the cream-like or soft texture of many formulas so that they can easily (and evenly) glide silicones and pigments onto the skin.
Who Should Use It: Anyone experiencing dryness or anyone who uses makeup, as long as they’re not allergic. “It is great for people with very dry and dull skin, especially those who have impaired barriers from eczema, seborrhea, psoriasis, and rosacea,” Chimento explains.
When You Can Use It: Isododecane can be applied twice a day topically, in the morning and at night during your skincare routine.
Works Well With: Virtually any other beauty product, as long as you’re storing it properly in a cool, dry area. “It is non-comedogenic and has a matte feel, so it is also great for patients that have oily skin and are acne-prone. Essentially, anyone can use it,” Chimento says.
Don’t Use With: According to Chimento, those with super-sensitive skin types or a known allergy to the ingredient should not use isododecane.
What Is Isododecane?
Isododecane is both a solvent and an emollient which, in short, means that it helps keep your skin hydrated and disperses other appearance-enhancing ingredients across the skin, Patel says.
“Isododecane is used as a solvent in the cosmetic industry since it carries silicones and pigments for makeup super well,” Patel notes. “And it’s used as an emollient for trapping in moisture on the skin’s surface.” And since it goes on your skin, you should probably know more about isododecane besides what it does for aesthetics.
Chemically speaking, isododecane is a colorless liquid hydrocarbon, Chimento says. “It is used in many common beauty, skin, and body care items to enhance the feel of them,” she explains, and it also distributes hues and skin-plumping silicones to your face.
You’ll likely find isododecane in a majority of your beauty products, including but not limited to moisturizer, creams, concealer, foundation, mascara, eyeliner, eyeshadow, lip gloss, lipstick, and more.
What Are the Benefits?
- Creates a more even tone: On the surface, your makeup will look visibly more even-toned and luminous when it contains isododecane, Chimento says.
- Strengthens the skin's barrier: Below the epidermis, you’ll feel that isododecane creates a stronger skin barrier, stopping moisture from escaping and reducing dryness or flakiness overall, she explains.
- Helps retain moisture: Isododecane helps the skin retain moisture, so it's excellent for dryer types.
- Doesn't leave a residue: Isododecane is formulated to glide on easily and glide off just as easily (so it won't leave behind a sticky film or residue).
- Creates a silky-smooth texture: Isododecane also plays a role in the way your makeup and skincare feel. “It imparts a silky smooth feel to products while giving a dry touch finish,” Chimento says. So the cream-like, supersoft texture of your moisturizer, concealer, foundation, etc.? That often comes from isododecane.
- Fast absorbing: Unlike some skincare products, isododecane quickly absorbs into the skin, meaning you lose less product.
- Non-irritating: For the most part, isododecane is non-irritating and safe for use on all skin types.
- Multiple forms of use: As isododecane is used in a wide range of topical products, there are plenty of options for how and when you can use it.
Side Effects of Isododecane
Sure, isododecane is synthetic. But our experts say that in limited quantities (like when you're using it in your beauty routine), it’s not going to do you any harm. “It is not absorbed into the body, so there is little data on the effects,” Patel says. “It has also been used for decades in beauty products, and there are no reported side effects to study.”
And for those of you with sensitive skin, you should be fine using products with isododecane, Chimento says. But if you’ve got more than one skin allergy or a history of allergies related to that specific chemical, you’re safer staying away.
“In most people, such small amounts don’t cause any significant side effects. However, even such trace amounts can cause contact dermatitis in very sensitive skin,” Chimento says, which is why she recommends checking with your doctor before using it if you’re concerned about sensitivity levels.
How and When to Use Isododecane
Essentially, feel free to use products with isododecane as you please, but be sure to store them properly. Patel recommends keeping them in a cool, dry place and not using them past their expiration date (they have a shelf life of about two to five years).
The Best Products With Isododecane
A mineral sunscreen made with fruit extracts and a specially-formulated micronized powder, which provides luminosity and minimizes the appearance of pores.
A Byrdie favorite, this tinted sunscreen offers broad protection and covers minor discolorations and imperfections.
This oil-free face lotion provides broad-spectrum protection and is a 100 percent mineral sunscreen, so it forms a protective barrier on the skin to help reflect UVA and UVB rays.
This retinol alternative is gentle enough for everyday use and can be layered with other products to further the exfoliating benefits.
Those with oily or combination skin will benefit most from this pore-clearing potion, which combines salicylic, niacinamide, and succinic acids to target imperfections and unclog pores without irritating the skin.
An anti-aging face moisturizer designed for sensitive and dry skin, this lotion contains lactobionic acid to gently exfoliate and firm the skin.
