What’s a Scalp Serum and Do I Need One?

Three years into a pandemic-induced cycle of on-again, off-again relationships with our hairdressers (and a mostly always-on relationship with capital S-stress), and our hair is probably in need of some serious help. While the pan certainly didn’t start the “skinification of hair” trend—where classic skincare ingredients like hyaluronic acid and niacinamide started appearing in hair and scalp products—it definitely accelerated people’s interest in taking extra good care of their heads.

Now scalp serums, which are super concentrated, easily absorbable formulations designed to treat the skin on your scalp, are seemingly everywhere. Some are leave-in, some you rinse out. Some you can use every day, and some are intense, short-term treatments.

“Scalp health and hair are inextricably linked because your hair follicles are in your scalp,” says cosmetic dermatologist Sonya Abdulla from DLK on Avenue in Toronto. “The health of your scalp skin dictates the health of your hair.”

Abdulla says the main complaints dermatologists see are excessively dry and itchy scalps, overly oily—sometimes pimply—scalps and unexplained bald patches. All of the above can be triggered by stress, pollution, genetics, hormonal changes like pregnancy and perimenopause. Over-washing your hair can dry out your scalp and disrupt the skin barrier, but under-washing your hair can lead to product buildup that plugs up your follicles. (Abdulla says how much you should shampoo depends on your hair type and how much you work out or sweat each day—but a good rule of thumb is if it seems greasy or you get debris under your fingernails when you run your fingers across your scalp, it’s time for a wash). We’ve all probably tried serums for our hair, but do you need a serum just for your scalp, too?

“The same way that some people have a very basic skincare routine for the face, it’s not unreasonable to take the same approach to the scalp,” says Abdulla. “But if you’re wanting to go a few steps further in maintaining your scalp health or to address targeted concerns, that’s where a serum can be beneficial.”

Abdulla says you should consult a doctor if you’re experiencing open sores or your scalp is super inflamed—do not try to Dr. Sephora that sh*t! If not, the kind of serum you should look for is one with ingredients that target your particular issue, like ginseng for stimulating growth or AHAs, BHAs and salicylic acid for getting rid of flakes.

Conclusion? I half suspect a scalp serum is just a good way to trick people into massaging their scalps more regularly—which can improve scalp health on its own by stimulating blood flow—but a serum makes it more fun. So if you’re reasonably happy with your hair and don’t have any scalp issues that are bugging you, you probably don’t need a serum. But if you have a specific concern, they can definitely help. Now please excuse me while I go cover my bald spots with a root spray.

The Inkey List Salicylic Acid Exfoliating Scalp Treatment

This lightweight, fragrance-free serum helps get rid of flakes and itchiness with salicylic acid, which gently exfoliates the scalp and balances out oi levels, while a mix of hydrating ingredients moisturizes it at the same time. But just like with your face, Abdulla warns that when it comes to exfoliating, less is more—over-exfoliating can make things worse. “There will always be exceptions, particularly if we’re dealing with diagnoses that are more advanced,” she says. “But typically, once to twice a week is the sweet spot.”

$19, ca.theinkeylist.com

Kérastase Specifique Serum Potentialiste

The hydrating serum is loaded with a healthy prebiotic and a vitamin C derivative to protect the scalp’s microbiome from the damaging effects of pollution and help hair adhere more strongly at the roots.

$80, kerastase.ca

Aveda Invati Advanced Scalp Revitalizer

Here’s something I learned from Abdulla that I never wanted to know: With every decade your hair follicles get a little sadder smaller, leading to ever-thinner hair. This formula tries to stave off the inevitable by using tangerine peel, Japanese knotweed, ginseng and turmeric to support hair’s natural keratin and amla leaves to make hair look more pumped up at the roots. It’s a leave-on formula that you’re meant to massage in daily, but it’s not greasy and can be used on wet or dry hair.

$90, aveda.ca

Moroccanoil Dry Scalp Treatment

This delicious-smelling rinse-out formula—geranium and lavender blend for the win!—is also formulated with salicylic acid to gently exfoliate the scalp. Vitamin E and argan oil are added to the mix for a moisturizing punch.

$48, sephora.com

JVN Complete Pre-Wash Scalp Oil

This nutrient-packed pre-wash oil from my personal bestie Queer Eye’s Jonathan Van Ness’s line uses sugarcane-derived hemi-squalane to strengthen hair, basil root extract to minimize breakage and neem extract and bisabolol to soothe itchy scalps. A yummy scent blend of amber and cashmere musk with lemon and mandarin doesn’t hurt either.

$38, sephora.com

Hair Rituel by Sisley Paris

Ok, this baby isn’t cheap, but at least it’s a time-limited program—kind of like a luxurious visit to French hair rehab. You use a few pipettes every other day for a month and then twice-a-week for maintenance to juice up your follicles with this super-light mix. The formula includes vitamins and minerals like vitamin H, known for treating hair loss, arginine (an amino acid that is part of the proteins found in hair keratin), and soothing alpha-bisabolol (a component of chamomile) to calm irritated scalps.

$265, sisley-paris.com

Next: The Root Cause of Thinning Hair and Hair Loss for Women