If you have fine, or thin hair like I do, you’ve might’ve subscribed to the *myth* that washing it less often will help stop excess shedding in its tracks (I’m 100-percent guilty of this). But according to dermatologists, skipping shampoos does way more harm than good—especially if you’re experiencing stress, hormone, or autoimmune disease-related thinning and hair loss. The reality is that maintaining a clean and healthy scalp is a mandatory prerequisite to thicker, fuller-looking hair. Which means you’ll want to drop the dry shampoo and get on a regular washing routine, ASAP.

But not just any shampoo will do, you’ll want to reach for something that gently cleanses and leaves hair feeling thick and strong from root to tip—like the Kérastase Bain Densité Shampoo ($40). The French hair care brand’s best-selling thickening shampoo claims to do the most for fine, thinning hair: wash away build up, boost the density of strands, and strengthen hair for your fullest, healthiest mane. And just like Kerastase’s other offerings, like the growth-boosting shampoo to the hydrating oil serum that quenches dry hair, pro hair stylists swear by it.

Kérastase, Bain Densité Shampoo — $40.00

The French hair care brand’s best-selling thickening shampoo claims to leave fine, thinning hair feeling fuller and stronger than before—for your healthiest, most lustrous mane.

LA-based celebrity hairstylist, Bradley Leake, whose client list spans reality TV’s biggest names (read: Chrishell Stause, Stassi Schroeder, Lala Kent and the queen herself, Ariana Madix) loves the Bain Densité Shampoo. “The Kérastase Densifique Bain Densité is simply a powerhouse of a shampoo,” he tells us. “[It’s] packed with incredible ingredients that treat, cleanse, and strengthen your hair.”

How it works

Take a look at the shampoo’s ingredient list, and you’ll find some familiar faces. Hyaluronic acid, for example, the skin-care world’s hydration hero,  plays a unique role in Kerastase’s Bain Densité Shampoo. “Think of Hyaluronic acid as a preventative treatment for your hair,” explains Leake. “It removes the risk of breakage and builds strength and volume.” The shampoo even contains ceramides, moisturizing superstars that help the lock in moisture while boosting shine and elasticity.

But the MVP of this thickening formula, according to Leake, is the shampoo’s special gluco-peptide. “People often neglect to care specifically for their hair cuticles, focusing instead only on repairing split ends or containing frizz,” he explains. “[Gluco Peptide] penetrates the cuticle to ensure that as hair grows, it’s strong and healthy from the inside out!” The gluco peptide essentially plumps up each and every strand, giving you stronger, thicker-looking hair.

Why we love it

We obviously love Bain Densité for its strengthening, strand-thickening powers, but it’s also a fantastic volumizing shampoo. “It’s a deep cleansing agent that will keep your hair looking flawless by preventing build up as your volume increases!” says Leake. Which means you’ll never have to worry about dirt, oil and styling product residue bogging down your hair and scalp. And unlike other thickening and volumizing formulas I’ve tried that strip my hair of any and all moisture in the name of bouncy lightness, Kerastase’s winning formula proves that you needn’t compromise hydration for fullness. It has a rich, fluffy lather that deeply cleans without drying out my hair—and the scent is divine, perfume-y in the best way. The result? Fabulously full and hair with that coveted salon-shine.

“I LOVE Bain Densite Shampoo,” gushes one Kerastase shopper in a 5-star review. “It is without a doubt the best shampoo I have used…It cleanses my hair without any harshness, creates fullness like I had in my 20s, and smells amazing!” Another shopper says that Bain Densité totally transformed her mature, fine hair. “I love everything about it. It’s thick and smells wonderful. It lathers beautifully,” she says in a 5-star review. “My very fine hair looks beautiful and shiny, and coupled with the other products in this line, [it has] transformed my flat lifeless hair into beautiful, healthy, shiny, and thick hair!”

To all my fellow fine, thin-haired folks—you need this thickening shampoo in your shower, STAT. To double down on the strand-plumping benefits, you can’t go wrong by pairing Bain Densité with the line’s matching Fondant Densité Conditioner ($46) too.