Your Hair Follicles Have a Sense of Smell—And This New Scalp Serum Taps Into That To Lengthen and Strengthen Your Strands

Photo: Stocksy / Marc Bordons
With the Well+Good SHOP, our editors put their years of know-how to work in order to pick products (from skin care to self care and beyond) they’re betting you’ll love. While our editors independently select these products, making a purchase through our links may earn Well+Good a commission. Happy shopping! Explore the SHOP

Back in 2018, scientists made a wild discovery—your hair follicles have a sense of smell. And they really like the smell of sandalwood. So hair-care brand Nioxin partnered with the scientist behind that discovery to create a scalp serum that's rich in woody, leathery scent. As your hair follicles sniff up the serum, they anchor into the scalp (reducing excessive shedding) and spend more time in the growth phase of the hair cycle.

"You don't really think about your hair having smell capability, but this is what makes this research so exciting," says Fatima Fahs, MD, a board-certified dermatologist in Canton, Michigan who works with Nioxin. "This is something that is going to empower both patients and consumers to be able to start to use something on their hair even before they necessarily notice hair shedding or even before they notice that their hair has gotten too bad."

The Nioxin Ultimate Power Serum ($50) is a leave-on scalp serum that can be applied when hair is wet or dry. To create it, the brand partnered with Ralf Paus, MD, a board-certified dermatologist in Miami, Florida, who co-authored the 2018 study that found that the outermost layer of our hair follicles have a receptor that is stimulated by smell.

Experts In This Article

"It's called an olfactory receptor," says Dr. Fahs. "Olfactory just means smell, and this olfactory receptor was sensitive to sandalore, which is a synthetic sandalwood odor. And we found that basically this receptor responds to sandlore and increases the production of a growth factor in this hair that prolongs the hair growth cycle."

At any given time, the majority of our hair is in one of three phases: anagen (growth), catagen (transition), and telogen (rest/shedding). "A normal patient should have about five to 10 percent of their hairs in this telogen phase," says Dr. Fahs. Sometimes, due to changes like illness, having a baby, stress, high fever, or surgery, this ratio shifts. "Instead of all those hairs being in that normal growth phase, a lot of them transition into that falling out phase. And so suddenly you're getting clumps and clumps of hair and it's very distressing," she says. The Nioxin Ultimate Power Serum increases the production of a growth factor for the scalp that prolongs that growth phase and prevents cell death that causes hair to go into that resting phase where shedding occurs.

Additionally, it causes hair follicles to anchor into the scalp. "This is kind of a newer term, but hair anchorage pretty much means that we are locking the hair into the root and holding it tightly," says Dr. Fahs. "It's allowing the scalp to have an increased root resistance so that you don't have excessive shedding."

What also sets it apart from minoxidil is the texture. Topical minoxidil is oily and sticky and can weigh down the hair and make it look greasy depending on your hair type and texture. This Nioxin serum is super lightweight and water-based "The consistency is a bit watery but absorbs and dries really fast," says Gabrielle Henderson, a hairstylist who works with Nioxin. "The product dries clear and I never have any issues with residue or flakiness."

Because it's water-based, it can be a bit tricky to use if you have naturally curly or coily hair and like to wear it straight. "I recommend applying Ultimate Power Serum to your scalp at night and then tying your hair down with a scarf," says Henderson. "This will ensure the hair won’t swell when trying to revert back due to it being compressed by the scarf, leaving your roots nice and straight."

These mechanisms of action are things that anyone can benefit from, even before any excessive shedding occurs. This sets it apart from the most widely available hair-growth topical, minoxidil aka Rogaine. Rogaine is applied daily to respond to genetic hair loss. If you stop applying it, you lose any and all growth it may have spurred. With Nioxin, you can use it both proactively and reactively regardless of the cause of hair loss.

This is super beneficial for those who are pregnant or postpartum.

"I'm currently pregnant and I like that I am able to do something rather than nothing" to reduce post-partum hair loss, says Dr. Fahs. " That is probably what makes it so exciting because you know, traditional Rogaine has minoxidil, and this is an ingredient we tell [pregnant and breastfeeding] patients they have to avoid."

It's also amazing for those who put stress on their hair through styling.

"For patients who do high-tension styling or, for example, who keep braids in for weeks at a time," says Dr. Fahs, "having a product like this to dispense throughout their scalp can be really nice because it kind of blends in pretty easy and also feels like a little more of a preventative insurance policy if you're gonna go ahead and take that risk."

In addition to sandalore, this serum has other scalp-and-hair-loving ingredients.

"It also has caffeine which is going to help maintain the skin barrier. And when you massage with caffeine, it can increase that blood microcirculation so it can prove the delivery of the product," says Dr. Fahs. "It has lauric acid which aids in nourishing the hair roots, so that can be helpful with preventing breakage. And people did report that they felt like they had less hair breakage, so it's probably the strength of that ingredient and then niacinamide as well, which also penetrates the hair roots and produces  stronger, thicker hair."

Whether you're experiencing excessive shedding or want to prevent it from happening, the Nioxin Ultimate Power Serum is the perfect addition to your hair-care routine.

But wait, there's more!
Want to be the first to hear about the latest (and greatest) SHOP product drops, custom collections, discounts, and more? Sign up to have the intel delivered straight to your inbox.

Loading More Posts...