The Most Effective Hair Growth Serum

A best-seller with more than 60,000 perfect five-star reviews, this treatment for scalp and hair loss is a top pick. It targets all forms of hair loss, including androgenetic alopecia, traction alopecia, telogen effluvium, and trichotillomania.

A combination of antioxidant-rich peptides, nourishing hyaluronic acid, and barrier-boosting niacinamide create the ideal environment for new growth while reducing hair breakage.

1. Kerastase Nutritive Lait Vital Serum

A high-nutrition ultra-light detangling conditioner for dry fine to medium hair. The conditioning formula contains lipids and vitamins to nourish, detangle, and smooth dry hair while keeping it lightweight. It also seals cuticles to maintain hydration for longer. It provides an intense nutrition care for your hair, leaving it soft and supple with incredible shine.

Millies Expert Tip: Lait Vital is a powerful light conditioner that nourishes and detangles without adding weight to your hair. It is infused with plant-based proteins, fatty acids, and vitamin E to nourish and strengthen the hair fibre. It also contains niacinamide (a derivative of vitamin B3), and glycerin to help lock in moisture.

Apply a quarter size amount of Lait Vital to washed and towel-dried hair, distribute evenly and leave in for 2-3 minutes then rinse thoroughly. If irritation occurs, reduce frequency of use. This product is best used after Bain Satin or Bain Satin Riche.

2. Necessaire Nourishing Scalp Elixir

A featherlight blend of botanical oils and extracts, this hair serum helps to calm a stressed scalp, lock in hydration and promote healthy, thicker locks. It’s free from phthalates, silicones and synthetic fragrance and it’s a great addition to your weekly wash routine. Just massage a few drops into the skin when your strands are damp.

This nutrient-rich formula is made with a blend of rosemary oil, azelaic acid and most effective hair growth serum panthenol, which help to promote healthy hair growth by strengthening the follicles. The serum also contains adenosine, which is a natural DHT inhibitor and it was formulated by trichologist Anabel Kingsley.

Necessaire was founded in 2018 by a former VP with 16+ years at Estee Lauder and the co-founder of beauty blog Into The Gloss. The brand was built around the idea that you should only use products that are absolutely necessary. Their products are free from parabens, phthalates, sulfates, silicones, petro-chemicals and synthetic fragrances. They’re also climate-neutral and plastic-neutral and their packaging is made with 85% post-consumer waste.

3. Nutrafol Hair Growth Serum

Nutrafol’s bestselling hair growth supplement has thousands of perfect ratings on Amazon and is beloved by stars like Alyssa Milano and Bethenny Frankel. It’s also a favorite among our experts, who recommend this serum for its ability to nourish and support visible hair growth. A nutrient-packed blend of rosemary, ashwagandha, sea buckthorn, and moringa oil helps to stimulate the scalp and promote healthy strands, while balancing hormone HAIR STYLING levels with saw palmetto and maca help prevent thinning or hair loss, as well as reduce the effects of menopause and perimenopause.

This fast-absorbing and lightweight serum is formulated with Ashwagandha exosomes that boost cell-renewal and naturally activate thicker and stronger-feeling hair in just 90 days. It also features clean ingredients such as pea sprout extract to strengthen the hair strands, reduce breakage, and minimize damage.

Nutrafol’s products are available in formulas for both men and women. The gender-specific supplements and topical formulas are designed to address the unique hormonal fluctuations that can cause a reduction in hair growth. The hair growth serum can be used alone or with a daily Nutrafol supplement to create an integrated approach to scalp health and healthier-looking strands.

4. Act + Acre Peptide Scalp Serum

Founded by trichologist Helen Reavey (who has clients that include Tilda Swinton and Alicia Keys), this haircare brand believes «the best way to thicken + grow your hair is to start at the scalp.» Its serum is made with a blend of copper peptides, bamboo extract, and shea butter for healthy growth; peppermint oil encourages blood flow to the scalp to support follicle health; and probiotics, prebiotics, and postbiotics bolster the scalp microbiome.

Lastly, swiss apple stem cells protect the hair follicles to minimize shedding and prevent early signs of thinning. The non-greasy formula is a hit with fans, who say their hairstylists are amazed at how healthy and thick their strands look.

This is one of our best-selling products, so it’s no wonder that it’s sold out most of the time. But it just restocked, and we’ve got it (and all of our other shopper-favorites) 25 percent off for you with code INSTYLE25. Shop it and other splurge-worthy items below. Or you can try it for 30 days, risk-free. Get a full refund if you don’t love it.

5. TRESemmé Growth Factor Serum

A hair growth serum is typically used on the scalp to increase the speed of hair growth, encourage new hair follicles into the active growth phase and increase hair thickness, says the expert at Plated. The best hair growth serums contain ingredients like peptides, niacinamide and antioxidants.

A common ingredient is dimethicone, which is a water-resistant and breathable silicone that forms a protective barrier on the skin without leaving a tacky feel. You want a hair growth serum with at least that amount of dimethicone, but you may also find some with added plant- or enzymatically-derived growth factors.

For example, TRESemme keratin smooth shine serum is infused with keratin and marula oil to help strengthen hair for less breakage and protect against damage. It can be used on wet or dry hair to detangle, boost shine and tame frizz. Salon stylists know that great style comes with a superior care routine foundation and this serum is designed to work from the inside out to deliver healthy-looking hair.