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The 13 Best Hair Growth Serums for Thicker Hair in Days
Packed with powerful ingredients, these are the scalp serums that really work.
Even if it seems like people don’t talk about it, hair thinning and hair loss are fairly common concerns. Whether the cause is postpartum, aging, nutrition, stress, illness, or some combination thereof, there’s a good chance the thickness of your hair has undergone fluctuations.
If you felt like the only options for thinning hair were minoxidil-based products like Rogaine, you’ll be happy to know the category has gotten a glow up. There are hair growth vitamins, which help from the inside-out, as well as hair growth serums, which are applied directly to the scalp. But keep in mind they may not work the same for everyone: "There's limited data on hair growth serums for thinning hair compared to FDA-approved minoxidil, but some preliminary data are very hopeful," Minnesota-based dermatologist, Jenny Liu, says. To kick-start your hair growth, we gathered 13 of the best hair growth serums on the market, including picks from Liu as well as celebrity hairstylist Clariss Rubenstein.
The Best Hair Growth Serums
The INKEY List Caffeine Stimulating Scalp Treatment
The INKEY List Caffeine Stimulating Scalp Treatment
Pros
- Great price
- Derm-approved
Cons
This overnight treatment is made with caffeine and redensyl to combat hair loss, as well as conditioning betaine. Liu recommends this inexpensive option for those with alopecia, also called androgenetic hair loss.
What the experts are saying:
“Caffeine has preliminary data to support hair growth, especially for androgenetic hair loss,” says the derm.
| Size | 5 oz/ 150 mL |
|---|---|
| Hair Type | Straight, Wavy, Curly, and Coily |
| Active Ingredients | Caffeine |
Stripes Ectoine Calming & Thickening Scalp Serum
Stripes Ectoine Calming & Thickening Scalp Serum
Pros
- Specifically formulated for hormonal hair loss due to menopause
Cons
This serum is specially formulated for those experiencing hair loss and thinning during menopause. It features a blend of effective ingredients, including hydrating ectoine and squalane, strengthening Indian gooseberry adaptogen, and pea peptide to promote thickening.
What the Reviewers Are Saying:
"It’s been amazing for my dry and flaky scalp! It feels really calming and soothing after I apply it, I hate to rinse it out. Not sure about thickening but it makes my scalp less tight and dry for sure!"
| Size | 50 mL / 1.7 fl oz |
|---|---|
| Hair Type | Dry, Thinning Hair |
| Active Ingredients | Ectoine, Squalane, Amla, Pea Peptide |
Monat Hair Thinning Defense
Pros
- Works quickly
- Fragrance-free
Cons
Rubenstein “loves” this serum from Monat containing caffeine, antioxidants, and melatonin. Plus, it has a lightweight consistency and is fragrance-free.
What the experts are saying:
“It promotes hair growth, density, scalp health, and is totally safe to use daily,” says the hairstylist.
| Size | 50 ml / 1.7 fl. oz |
|---|---|
| Active Ingredients | Caffeine, Melatonin, CAPIXYL, Biotin |
Vegamour GRO Hair Serum for Thinning Hair
Vegamour GRO Hair Serum for Thinning Hair
Pros
- Impressive clinical results
Cons
Vegamour is renowned in the hair-growth space, and the clinical studies support it too: 52 percent of subjects saw an increase in the appearance of hair density, while 76 percent saw a reduction in hair shedding. Plus, it's pleasantly scented with bergamot essential oil
What the reviews are saying:
"I’ve only been using Gro for three months and already have amazing results! I had severe postpartum hair loss that just wasn’t returning after having my baby 18 months ago. My thinning areas haven’t filled in completely yet, but if I’ve had this much success in only 3 months I can’t wait to see it at the six month mark!"
| Size | 1 oz/ 30 mL |
|---|---|
| Hair Type | Straight, Wavy, Curly, and Coily |
| Active Ingredients | Turmeric, N. benthamiana, Red Clover/ Mung Bean |
Nécessaire The Scalp Serum
Nécessaire The Scalp Serum
Pros
- Skincare ingredients
- Soothes the scalp
Cons
- Needs to be used consistently in order to see results
If you hate the feeling of heavy products on your scalp, consider this lightweight, leave-in formula that feels more like a face serum. It features a five percent biomimetic peptide blend to support thinning, plus hyaluronic acid to hydrate, and green tea to soothe itchiness. Plus, it won't leave any residue on your scalp.
What the reviews are saying:
"I love how lightweight this is. It almost feels like water and has no scent. It is not greasy so I can apply it between washes on dry hair." —Emily R.
| Size | 2 oz |
|---|---|
| Hair Type | All Hair Types, Including Color-Treated |
| Active Ingredients | Biomimetic Peptide Blend, Hyaluronic Acid, Niacinamide and Vitamin B3 |
Inala Power Potion
Inala Power Potion
Pros
- Great for textured hair
- Lightweight formula
Cons
This daily treatment has a bevy of strengthening ingredients like rice water extract, biotin, and arginine to nourish the scalp and roots. It's also oil-free, and can be applied to wet or dry hair.
What the reviews are saying:
“I swear by The Inala Power Potion. My edges are back and my problem areas have new growth.” —Ebone
| Size | 1.5 fl oz |
|---|---|
| Hair Type | All Hair Types |
| Active Ingredients | Rice Water extract, Biotin, and Arginine |
Act+Acre Cold Processed Stem Cell Serum
Act+Acre Cold Processed Stem Cell Serum
Pros
- Impressive clinical results
Cons
- Some said it made their scalp feel greasy
Act + Acre, a brand built on scalp care, uses two percent Swiss apple stem in its scalp serum. Use it daily to see less thinning and more hair density in just 30 days, and to soothe the scalp.
What the reviews are saying:
"I haven’t been using this product for very long, but I am already seeing less hair in my shower drain. And my stylist has noticed how much better my hair looks."
| Size | 2.2 fl oz/ 65 ml |
|---|---|
| Hair Type | Straight, Wavy, Curly, Coily |
| Active Ingredients | Swiss Apple Stem Cells, Aloe Vera, Bamboo Extract |
Pros
- Great price
Cons
This affordable serum is made with three percent Redensyl and two percent Capixyl (hence the name), to quickly absorb without leaving a residue. And while some hair growth products can have a clinical smell, but this highly rated serum has a fresh fragrance.
What the reviews are saying:
"I have been using this for almost a year. It does take a little time but it works. New hair growth comes in and you just need to keep at it. My thinning spot on my crown has filled in slowly." —Connie M.
| Size | 30 ml |
|---|---|
| Active Ingredients | Redensyl and Capixyl |
OUAI Hydrating Scalp Serum
OUAI Hydrating Scalp Serum
Pros
- Skincare ingredients
- Soothes the scalp
Cons
Leave it to Ouai to have yet another product we need to stock up on. With peptides and hyaluronic acid, this hydrating serum is like much-needed skincare for your scalp, and helps create fuller-looking hair in 90 days.
What the reviews are saying:
"This started to fill in my thinning hairline with noticeable color from baby hairs within a couple of weeks. I was shocked! I use it once a day at bedtime, but I also wash my hair every day because it’s a sebum factory. I had a hard time with the price but am so glad I made the investment." —SizzleMN
| Size | 2 oz / 60 mL |
|---|---|
| Hair Type | Straight, Wavy, Curly, and Coily |
| Active Ingredients | Hyaluronic Acid, Red Clover Flower Extract, Peptides |
Agent Nateur Holi(locks) Strengthening Hair Growth Serum
Agent Nateur Holi(locks) Strengthening Hair Growth Serum
Pros
- Helps strengthen hair
Cons
A combination of watermelon seed, pumpkin seed, green tea, and more extracts make up this formula. You can leave the treatment oil on for as little as 30 minutes, or as long as 12 hours; either way, you’ll start noticing less fallout and stronger hair in 12 weeks.
What the reviews are saying:
"This product is magical. I’ve used it 2-3 times a week for six weeks and it’s greatly improving my hair." —Stella9907
| Size | 1.7 fl oz |
|---|---|
| Hair Type | Thin/Weak, Damaged/Dry |
| Active Ingredients | Follicusan, Capixyl, Redensyl, Beracare ARS Hair Serum, Pumpkin Seed |
Dr. Barbara Sturm Anti-Hair Fall Scalp Serum
Dr. Barbara Sturm Anti-Hair Fall Scalp Serum
Pros
- Skincare ingredients
- Lightweight formula
Cons
The coveted skincare line is known for its hyaluronic serum, but don’t discount the scalp serum. Made with camellia and larch extracts to strengthen the hair shaft, it also has Pro-Vitamin B5 to reduce breakage.
What the reviews are saying:
"It is the first serum I tried that really helps and I will continue using it as long as needed. It also helped a lot with my itchy scalp. So glad I found this." —Delia M.
| Size | 50 ml |
|---|---|
| Active Ingredients | Glycerin, Panthenol, Purslane Extract, Cationic Hyaluronic Acid, Sunflower Seed Sprout Extract, Tara Extract, Camellia Extract, European Larch Extract |
Better Not Younger Superpower+ Advanced Hair Densifying Scalp Serum
Better Not Younger Superpower+ Advanced Hair Densifying Scalp Serum
Pros
- Multitasking formula
Cons
Don't love an oil-based formula? This has a refreshing gel texture that absorbs easily into the scalp. In addition to rosemary oil—which has been studied for its hair-growth properties—it also features apple cider vinegar, which the real ones know is a must for a balanced scalp.
What the reviews are saying:
“Don't know if my hair is getting thicker yet, but my hair's texture is so soft and silky. And my scalp feels nice and hydrated. And the voume and bounce has returned to my hair.” –Velvet
| Size | 2.0 fl oz |
|---|---|
| Hair Type | Thin |
| Active Ingredients | Rosemary Extract, Apple Cider Vinegar, Proprietary Superpower Blend |
The Ordinary Multi-Peptide Serum for Hair Density
The Ordinary Multi-Peptide Serum for Hair Density
Pros
- Great price
- Highly rated
Cons
- Some reported breakouts where it was applied
This popular serum costs less than $20, and boasts over 550 five-star reviews. Plus, it has scalp-approved ingredients like peptides and caffeine.
What the reviews are saying:
“I've been applying it at night and I wake up with my hair feeling like it has more volume without being greasy. My bald spots are finally disappearing as well.”
| Size | 2.0 fl oz |
|---|---|
| Hair Type | All Hair Types |
| Active Ingredients | Argenine, Caffeine, Castor Oil |
Frequently Asked Questions
What ingredients should you look for in a hair growth serum?
Several ingredients can help in the hair-growth journey. "Caffeine and topical pumpkin seed oil extract has been demonstrated in small studies to demonstrate efficacy, plant derived flavonoids and other antioxidants possibly as well," Liu says. Rubenstein echoes the caffeine recommendation, and adds biotin to the list. "Biotin supports hair health. You need things that stimulate growth but also support the new hair," the hairstylist says.
How do you apply hair growth serums?
In general, you apply directly to the scalp, then massage them in (enjoy the extra moment of self-care). But be sure to read the instructions, as some products should be washed out, while others are left in. Use once or twice a week, or even daily depending on the product. "Depending on what’s in it the frequency of suggested use may vary," Rubenstein says.
Meet the Experts
- Jenny Liu, MD, FAAD, is board-certified dermatologist based in Minnesota.
- Clariss Rubenstein is a celebrity hairstylist who has worked with Jennifer Garner, Dakota Fanning, and Mindy Kaling.
Lindy Segal is a beauty writer and editor. In addition to regularly contributing to BAZAAR.COM, she also writes for Glamour, People, WhoWhatWear, and Fashionista, among other publications. She lives in New York City with her Chihuahua mix, Barney.
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