The Growth Serum Shoppers Use for "Fuller, Shinier, and Glossier" Hair Is on Sale for InStyle Readers

Despite having a multi-step skincare routine that involves serums, acids, and high-tech tools, I’d never considered showing that much care towards my hair. Every once in a while I’d throw on a hydrating hair mask for a few minutes and maybe I’d apply some oil, but at the end of the day I thought, “this is what my hair is and I just have to accept it,” — even as I watched one strand after another find their way to the drain each shower.

Even though so many women experience hair loss, few people talk about it (or their approach to fixing it). I think, like me, most people just accepted thinner hair as their fate. But according to the shoppers of one trichologist-founded haircare brand, there’s an easy and effective treatment, and it’s currently on sale just for InStyle readers.

Right now, everything at Act + Acre is 25 percent off with the code INSTYLE25 at checkout, including the brand’s famous Stem Cell Scalp Serum, this newly-launched hair-thickening treatment, and even the always-sold out scalp-cooling serum.

Cold Processed Stem Cell Scalp Serum

The Cold Processed Stem Cell Scalp Serum promotes thickness and regrowth by repairing the scalp’s microbiome through apple stem cells, which the brand says is proven to protect hair follicles, hydrating hyaluronic acid, and bamboo extracts. And according to shoppers, it’s made their hair “fuller,” “shinier, and glossier.” “It works. Period,” wrote one customer who said that it didn’t just stop their hair loss but actually caused new growth. “My hairdresser was also impressed and said how he’s never really seen anything that works for hair growth until now,” they added. “I see new hair growth and my hair has never been softer,” wrote another fan while one person dealing with postpartum hair loss wrote that “when [they] started using this serum [they] noticed a lot less hair fallout and some new growth.”

Cold Processed 3% Stem Cell Peptide Treatment

The Cold Processed 3% Stem Cell Peptide Treatment is one of Act + Acre’s newest launches, but it’s already on its way to becoming a shopper favorite, with one customer even deeming it the “holy grail treatment.” “I’ve been struggling with hair loss and hair thinning around my part and temples ever since getting Covid, and I swear this treatment is the only thing that's actually caused new growth for my hair,” they wrote, adding “[that they]’ve noticed such a difference in the overall thickness and feel of [their] hair!” And according to another customer, the treatment is “easy to use, cooling, soothing, and hydrating…absorbs fully, doesn't leave…hair sticky,” and doesn’t irritate the scape. “[And] above all, it works,” they gushed, writing, “I see less fallout and new growth.”

Cold Processed Microbiome Cooling Scalp Serum

Ever since launching this scalp-calming serum, it’s almost always sold out. But right now, it’s in stock and 25 percent off. The Cooling Scalp Serum was formulated to reduce itching and dandruff, with one customer calling it “THE solution for [a] dry scalp.” “This is the only product I've tried in years that calmed my scalp and decreased flaking,” said another fan, while one other customer called it “instant relief.” “I have psoriasis and eczema on my scalp and this really relieves the itching immediately,” they raved.

Everything from Act + Acre is on sale just for our readers with the code INSTYLE25. Shop more favorites including the Scalp Detox Oil, Anti-Frizz Leave-In Conditioner, and the curl cream below.

Vitamin E Scalp Detox Oil

Cold Processed 2% Squalene Anti-Frizz Leave-In Conditioner

Cold Processed Soft Curl Lotion

Cold Processed BHA Salicylic Acid Scalp Exfoliator