The Ordinary Hair Serum Is TikTok's Latest Hair Growth Secret

The Ordinary is no stranger to TikTok fame. The beauty brand has repeatedly gone viral for its surprisingly affordable skin-care products containing science-backed ingredients. But you don't want to overlook the brand's hair products, particularly one product that's become a fan favorite: The Ordinary Multi-Peptide Serum for Hair Density (Buy It: $18, sephora.com).

If you're someone with fine hair who dreams of thicker, more voluminous strands, The Ordinary hair growth serum was created with you in mind. Plenty of TikTok users and beauty influencers have all raved that it lives up to its promises after testing it for months. Taylor Rose (also known as @thehealthyhygge on TikTok with over 700 thousand followers) posted a video about their experience using the serum for two and a half months. Rose prefaces the video by saying, "it really freaking works," and goes on to show before and afters of their hairline, which is noticeably more full in the present day.

Rose's testimonial is just one of many across the app. Another user, @Sarah_Scotty, racked up more than a million views on their video featuring The Ordinary hair serum and said their hair is "the thickest and healthiest it's been in a while." Even a Shape editor, Akeesha Williams, with type 4C curls has seen major results in her hairline after two months proving it also works well for all hair textures.

The formula contains various ingredients with hair benefits, such as Redensyl, which activates hair follicle stem cells to improve hair growth, increasing the number of strands on the scalp aka hair density.It also includes Procapil to help increase blood flow to the scalp, and Baicapil to stimulate hair growth and increase hair density.

"This formulation contains various peptide complexes and incorporates several different technologies," explains Marisa Garshick, M.D., a board-certified dermatologist at MDCS Dermatology. "Peptides are shorter chains of amino acids that strengthen the scalp hairs. Since peptides stimulate collagen production, this can improve the overall health of the hair, including the strength and thickness, as collagen helps to support the hair follicle and natural proteins in the hair. Additionally, when applied topically, peptides may also help hydrate the scalp and hairs, making them appear healthier."

Other ingredients in The Ordinary hair serum formula include caffeine and castor oil. Castor oil helps to promote healthier and stronger hair because it uses ricinoleic acid, a type of fatty acid, to boost circulation in the scalp, says Dr. Garshick. Studies also suggest that caffeine can boost circulation and inhibit DHT, a hormone that plays a role in hair loss.

The Ordinary Multi-Peptide Serum for Hair Density 

The brand recommends applying a few drops of The Ordinary hair serum, massaging the formula into your scalp thoroughly, and leaving it in the hair overnight — and for best results, use it every night.

While some users have noticed changes after using The Ordinary hair serum for hair growth for a couple of months, results vary. "While changes in hair health can be seen within a few applications as a result of hydrating the hair, other changes can take several weeks to months to see a difference," says Dr. Garshick. "It's not unusual for changes related to hair and scalp to take up to three to six months, so it is always best to be consistent and stick with it to determine if it is working." In one review with nearly 500 thousand views, YouTuber Doro Cubillo says she started seeing a difference after three months of using the formula and continues to see "thicker and fuller hair" after using it for five months.

"With all hair serums and topical products, it is important to set expectations, but this lightweight formulation is easy to apply and is formulated with various ingredients that work together to improve hair health through different mechanisms," says Dr. Garshick. So, if you're looking for an affordable and easy way to get thicker hair, The Ordinary Multi-Peptide Hair Serum may be the answer to your prayers.