“Now that I’m styling my hair more often, I’m noticing some hair breakage at the top of my hair where I tend to pull it the most. This serum keeps that area hydrated and adds some shine to my strands. I’ve also noticed that my hair normally gets greasy after a day, but when I started using this Kérastase hair serum, my scalp stayed fresh for longer,” says Glamour’s Calle.
7. Best Hair Growth Serum for Hairline: Act + Acre Cold Pressed Stem Cell Scalp Serum
Original video from Alanna Martine Kilkeary testing Act + Acre Cold Pressed Stem Cell Scalp Serum
Original photo from Alanna Martine Kilkeary testing Act + Acre Cold Pressed Stem Cell Scalp Serum
Original photo from Alanna Martine Kilkeary testing Act + Acre Cold Pressed Stem Cell Scalp Serum
- What we like: Visibly combats hair thinning; makes hair appear fuller; clinically tested on ages 18 to 59
- What could be improved: Texture is slightly sticky but dries down fast with no residue
“I first heard about this pressed stem cell serum when it launched a few years ago, and I’ll be honest, it kind of seemed a little too good to be true,” shares Glamour commerce writer Alanna Martine Kilkeary. “It has a lot of lofty claims, so I was apprehensive about how well it could actually work.” Those claims include clinical trials with 90% of participants showing increased hair growth in six weeks, 100% expressing increased hair thickness, and 100% expressing stronger, healthier hair. Luckily, Kilkeary’s expectations did not fall short.
“I tried it for the first time about two years ago when I was experiencing hair thinning around the crown of my head, and applied it at night every day for a few months,” she says. “After that trial, I instantly saw hair growing in the applied area, and now I can’t go a night without it. It’s made such a huge difference in my hair health, and the application is easy to incorporate into any hair care routine, too, which experts say is very important.”
“Consistency is key when using scalp serums, and they work best when paired with other healthy hair practices like gentle washing,” adds Dr. Rambhia.
8. Best Hair Growth Serum for Shedding Hair: The Ordinary Multi-Peptide Serum for Hair Density
Original video from Alanna Martine Kilkeary testing The Ordinary Multi-Peptide Serum for Hair Density
Original photo from Alanna Martine Kilkeary testing The Ordinary Multi-Peptide Serum for Hair Density
Original photo from Alanna Martine Kilkeary testing The Ordinary Multi-Peptide Serum for Hair Density
- What we like: Reasonable price makes it far more accessible than other options
- What could be improved: Can feel slightly sticky
Dr. Yadav is a fan of this affordable option, specifically calling out the many protein-building amino acids and three lab-made complexes on the ingredient list. Those complexes—procapil, redensyl, and baicapil—all work to promote thicker, stronger hair by targeting stem cells and human fibroblasts, and increasing blood flow in the scalp, Dr. Song explains. The concentrated formula also features caffeine to improve hair density and uses a lightweight, emollient base for efficient scalp penetration.
“As someone with a very flat hair type myself, I was excited to give this peptide serum a whirl to see if it added bounce and thickness,” says Glamour’s Kilkeary. “The good news: My hair actually did look thicker post-application, so much so that I put on a headband to keep it from falling toward my face. This serum also did wonders for my typically knotty hair during the winter and hydrated my roots even after just one application and blow-dry. I’ll definitely continue to use this one throughout the colder months to keep my hair looking resilient, strong, and velvety.”
9. Best Hair Growth Serum for Baby Hairs: Harklinikken Hair Gain Extract
Original photo from Ariel Wodarcyk testing Harklinikken Hair Gain Extract
Original photo from Ariel Wodarcyk testing Harklinikken Hair Gain Extract
- What we like: Each formula is custom-blended to suit your hair care concerns
- What could be improved: Expensive; can only be purchased online or at a Harklinikken hair clinic
“I recently had the pleasure of visiting the Harklinikken New York Clinic, where I met with an expert to receive an in-depth scalp analysis and talk through some of my hair and scalp concerns,” says Wodarcyk. “The personal approach instantly put me at ease; I explained that I deal with a very dry, flaky scalp in the fall and winter; some greasiness at the roots; and dry, tangle-prone ends. Using that information, my expert sent me home with a trio of products: the Balancing Shampoo, the Daily Conditioner, and a custom-blended Hair Gain Extract. After using the extract alone and in tandem with the other products for a little over a month, I’ve noticed a surge of new baby hairs at my scalp and no more flakes. In fact, it’s the best condition my dry, sensitive scalp has ever been in. My hair also appears less greasy, even when I’m overdue for a wash—it’s like this serum perfectly balanced my scalp’s microbiome.”