The Haircare Products Borrowing Your Favorite Skincare Ingredients

Taking care of your skin no longer stops at your face. Haircare companies are now taking skincare’s lead by focusing on ingredients in their lineups that might usually be associated with the skin, like hyaluronic acid, salicylic acid, collagen, and niacinamide. While the needs of the skin and hair are different, the same treatment concepts can be applied to both areas—after all, the secret to beautiful hair is a healthy scalp, which is an extension of your skin. While traditional haircare targets therapeutic hair and scalp concerns separately, the latest haircare-skincare hybrids approach it in a more comprehensive manner, by providing solutions to protect and strengthen strands while maintaining a healthy scalp environment.

A stream of brands, from luxury labels Sisley and Omorovicza to cult, indie faves Sunday Riley and Drunk Elephant, have dipped their toes into the space as well. “I saw a gap that I wanted to address—there were tons of products designed for improving the hair, without looking at the overall health of the scalp,” Riley tells W, regarding the debut of her namesake skincare-haircare collection. “The scalp and the hair are two halves of a whole—you can’t have healthy hair growth without a healthy scalp.”

Dermatologist Dr. Iris Rubin also took a holistic approach when she founded the non-comedogenic, clean haircare brand Seen, whose products include good-for-skin additives such as bisabolol, a skin-soothing naturally derived ingredient, and squalane, a silicone substitute derived from plant sugar. “Your hair products can get on your scalp, face, and back. Even the rinse-off ones can leave an invisible residue, which in turn can cause breakouts, irritation, and scalp issues,” she says.

Just like you'd choose a skincare product with a specific type of problem-fighting ingredient, you should do the same when making selections for your tresses. In skincare, you aim to treat, nurture, and improve the quality of the skin with active ingredients, nutrients, and soothing botanicals. The same type of love is needed for the scalp and mane.

Still confused on how hero ingredients originally derived for your epidermis can be beneficial in your haircare routine? Hair and skincare experts spill intel on why certain ingredients are making big waves on the mane scene, below.

Micellar Water

Micellar cleansing waters are gentle enough for sensitive skin and effective in removing all traces of makeup while cleansing your face. The same technology used in facial cleansers is now being incorporated into shampoos that can be used for all hair types, even in those with chemically treated, dry or brittle manes. Micelles are tiny balls of cleansing oil molecules suspended in soft water. “Their outside is water soluble,” explains Dr. Joshua Zeichner, an associate professor of dermatology at Mount Sinai Hospital in New York City. “But the inside is oil soluble. When they come in contact with the hair, the oil soluble inside attaches to dirt and residue to remove it from the hair.”

Hyaluronic Acid

Hyaluronic acid is a superhero ingredient when it comes to your skin, scalp, and hair. It’s a lightweight humectant that deeply hydrates and binds moisture to cells. It can also draw moisture from air to keep your skin moist, holding almost 1000 times its own weight in water. “Think of it as a sponge that pulls in hydration to soften and plump the hair shaft itself, which can make the hair appear fuller and softer,” says Dr. Zeichner.

AHAs and BHAs

Although dead skin cells naturally shed and are replaced by newer ones, physical or chemical exfoliation can help expedite the process by increasing cell turnover and getting rid of any epidermal build up. Scalp exfoliation is particularly helpful for those with dry skin, dandruff or oily hair. AHAs and BHAs are chemical exfoliants that can be used in the reduction of flakes and in unclogging follicles of excess sebum, styling gunk, or Keratin debris.

Salicylic acid is a beta hydroxy acid (BHA), and is peripherally similar in concept to an alpha hydroxy acid (AHA). “They both dissolve the bonds that hold dull, dead skin cells on the surface of the skin, letting it gently shed, revealing a smoother, brighter [layer] underneath. The difference is that while AHAs are water soluble and work on the surface of the skin, BHAs are oil soluble and can penetrate into pores—meaning they work on the inside as well as the outside—which is particularly helpful for those with an oily scalp or are prone to scalp acne,” says NYC-based board-certified dermatologist Dr. Hadley King.

Collagen

Collagen is the key to a youthful complexion. It’s an essential building block of skin, but it naturally depletes with age. And, because of its large molecular size, it’s unable to penetrate through skin when applied topically. However, according to Dr. Zeichner, it does make for an excellent skin protectant and has moisturizing benefits that is helpful in addressing a dry scalp. “It coats the hair shaft to soften and strengthen it,” he notes.

Peptides

Peptides are chains of amino acids and are the building blocks of proteins naturally found in your hair and skin. “When hydrolyzed proteins are applied topically on the hair, they can help fill in damaged areas of the hair shaft, temporarily boosting its strength,” says Dr. King. Comparatively, some peptides are small enough to seep past the hair’s outer cuticle layer, into the deeper cortex “and bind with keratin, making them more resilient for a while”—well, at least until you rinse the effects away with your next shampoo.

Niacinamide

Niacinamide (aka vitamin B3) improves skin tone and texture and supports the skin barrier to help keep moisture locked in. It’s also a great anti-inflammatory agent. “When looking at your haircare, if you suffer from inflammatory skin diseases, applying niacinamide to your scalp can help reduce any redness and also help prevent inflammatory hair loss. There’s also some research that found that when applied topically there is a significant increase in hair fullness,” explains Dr. Orit Markowtiz, a board-certified dermatologist and founder of OptiSkin. “It may help inhibit oil production, which is helpful for those with excess scalp sebum,” adds Dr. King.

Vitamin C

As we age, our bodies produce less collagen. But in order to create it, says Dr. Markowitz, “Our body needs vitamin C,” a powerful antioxidant that provides anti-aging benefits. And because hair growth is a function of epidermal stem cells, the use of vitamin C may give cells a youthful edge. “Collagen is an important part of our hair structure, so using a product topically that contains vitamin C has the potential to stimulate the hair follicle and hair growth.”

Moreover, antioxidants, such as vitamin C, may shield hair against the damaging effects of the sun. “There’s data to suggest that free radical damage from UV light exposure can damage keratin in the hair shaft leading to weak, brittle strands,” shares Dr. Zeichner.

Caffeine

The hair on our scalp grows cyclically and follows three phases: an active growth phase called the anagen phase, a transitional phase where the hair growth slows called the catagen phase and a resting phase called the telogen phase. “When you experience thinning hair beyond normal shedding, your hair has been in the catagen phase [for an over-extended period of time]. Studies have shown that caffeine can help pin hair in the anagen phase, by blocking the DHT hormone that precipitates hair loss,” states Mark Curry, a co-founder and lead formulator of the Inkey List, a relatively new-to-market skin and hair care brand.