Beauty Hair Hair Products & Tools Shoppers With Thin Hair Say This $11 Thickening Serum "Saved" Their Strands It’s a “hidden gem” for more body. By Rachel Nussbaum Rachel Nussbaum Instagram Twitter Rachel is a journalist, writer, and editor who specializes in the beauty and wellness industry, writing about the best, safest products the industry has to offer for InStyle, Byrdie, and Shape. InStyle's editorial guidelines Published on June 24, 2022 @ 03:00PM Pin Share Tweet Email We independently research, test, review, and recommend the best products—learn more about our process. If you buy something through our links, we may earn a commission. Photo: Getty Images I'm no stranger to the phenomenon of losing a strange amount of hair: I've been a prolific shedder since the '90s, and am responsible for an untold number of empty Drano bottles. Between my three cats and myself, there's a lot of loose hair floating around these parts, so I'm always on the lookout for potential remedies. One that has reviewers impressed? Pacifica's Scalp Love Rosemary Mint Serum. According to users of the $11 soother, the "hidden gem" makes a "huge difference" for super-fine, thinning hair, and leaves roots looking "perky" and full. People at both Amazon and Ulta were dazzled by the effect: As one person commented, it "saved" their hair from excessive shedding, and filled in thin spots. "My hair overall became really thick, soft, healthy, and longer," they added. Another fan said that after trying minoxidil without much success, they tried the serum on a whim; after several months, they saw new hairs sprouting all over. That makes sense, per studies on rosemary oil, which is the second ingredient in Pacifica's formula. A 2015 randomized, controlled trial published in the peer-reviewed journal SkinMed compared the effect of rosemary oil versus minoxidil; it found that participants in both groups experienced a "significant increase in hair count" after six months, while a 2013 animal study found the ingredient helped with testosterone-influenced hair loss. Courtesy Shop now: $11; amazon.com and ulta.com So while the evidence isn't as robust as that for minoxidil, which is the only FDA-approved medication for hair loss in both men and women, there is some scientific backing for rosemary oil's effect on growth — and customers are pleased with the serum's results. As a reviewer going on a month of use wrote at Ulta, their hair is regrowing following postpartum hair loss, and more people commented on the "super shiny and soft" effects it created. The "noticeable amount of new growth" is a happy surprise for those with fine hair, a different shopper wrote, and it also calmed their dandruff and oiliness. Aside from rosemary oil, the formula features panthenol, vitamin C, aloe, and hyaluronic acid, and extracts from meadowsweet, witch hazel, sage, coltsfoot, yarrow, mint, liquorice, thyme, and horsetail. As a last fan wrote, the combination gave them more body, despite their hair having grown more fine with age. If you'd like to try it for yourself, get Pacifica's Scalp Love Rosemary Mint Serum for $11 at Amazon and Ulta Beauty.