3 Editors Try The Ordinary Hair Serum. Here Are Their Honest Takes

• Longest hair length at start: 14.8 inches
• Longest hair length at end: 16 inches

“The hair along my temples and at my natural part has been looking a little sparser in recent years, so I’ve been trying to encourage regrowth. I have very fine hair that breaks easily, so I was also interested in making my hair appear less stringy and a bit fuller. Day-to-day, I normally use shampoo, conditioner and heat protectant spray on the rare occasions I style it (about once a week).

The serum felt very light and runny, like a thin oil. It made my hair a bit greasy at first, but [when I] rubbed it in with a scalp massager ($18), the oily roots would disappear within half an hour. In its place, I’d have a bit more volume—likely from the serum and massager bolstering my roots a bit.

With a 9-month-old at home, I’m in the stage of postpartum hair regrowth. I expect to see baby hairs sprouting, though since using the serum, it seems there’s more of them—something my stylist commented on without me mentioning it. I’m seeing much heartier regrowth than when my first child was born, particularly where I’d been applying the serum directly. In the past, I had a few baby hairs here and there that grew back, but this time around, since using the serum, I have a fuzzy little lion’s mane popping up.

However, I think I can attribute most of the fuller, thicker hair to the fact that the product is so lightweight. That, plus the act of massaging it in really lifted my roots. My hair looked less wispy and flat, which was the end goal, so I’m happy with the results. I plan on using the serum for a few more months, just to see how it affects my hair long-term.

My one caveat is that I often want to use the serum right out of the shower as part of my get-ready routine, but it needs to be applied to a clean, dry scalp. That’s worth noting, just because it requires a little extra planning—and because you’ll need to budget in time to let the product settle in and dry, so you don’t have greasy roots.

• Longest hair length at start: 9 inches
• Longest hair length at end: 10 inches

My hair is very fine and straight with a slippery texture. The right side has always felt thinner than the left, especially near my temple. I was hoping the serum would address that thinness, especially since my 9-month-old is always tugging at my hair. My haircare routine consists of shampoo and conditioner, plus a leave-in conditioner to detangle when I brush my hair out of the shower.

Though the serum wasn’t greasy out of the bottle, I didn’t love the way it left my hair feeling after use. I kept it concentrated to one area, but I think if I were using it all over, I would need to wash my hair every morning (which I try to avoid). Regarding efficacy, I think I’d need to use the serum longer to see if it really works. While I experienced increased length, I didn’t notice a major change in density after two months. Having tried all sorts of “thickening” products and talking to my hair stylist about it, I can’t see the serum actually changing the thickness or fullness of my hair strands—that’s just genetics for me. I don’t think I noticed much change.

Lastly, this isn’t necessarily a con, but I think it’s important to have realistic expectations going in. While it’s helped with hair growth overtime, the serum isn’t an instant miracle. Optimal results will require consistent, long-term use.

• Longest hair length at start: 13.75 inches
• Longest hair length at end: 15.5 inches

My hair is fine and has always lacked density. In the right light, you can see straight through to my scalp. And volume? Forget about it. I’m always looking for products that will encourage hair growth to help with the density problem. (Because no product will make your hair thicker.) My haircare routine isn’t elaborate: Shampoo, conditioner and whatever hair product I’m testing at the moment. When styling, I will use heat protectant and pile on the volumizing products, including mousse and texture spray.

Regarding the serum itself, I found it lightweight and not greasy, though it did momentarily leave my fingers tacky after I had applied it to my scalp. While Candace and Katherine noted that their roots looked greasy, I thought mine simply looked wet. However, it dried quickly and didn’t weigh my hair down. Similarly to Candace, I saw that my roots were lifted significantly, likely thanks to the aggressive massaging.

In terms of efficacy, I also echo the sentiment of my fellow editors in that the serum did encourage hair growth, but I will have to continue using it long-term to see if it affects density. My hair grows very slowly. Based on pictures from last year, I calculated that it grows roughly ¼ inch per month, compared to the average 0.41 inches. However, in the roughly eight weeks that we tested the peptide serum, my hair grew about 1.75 inches, or 0.89 inches per month, surpassing the average. Overall, I think the serum is a good value, delivering on the promise to aid hair growth at a friendly price point.