Over the last few years, one ingredient has seemed to infiltrate the hair styling community more than any other. It’s shown up on red carpets, TikTok feeds, and drugstore shelves, and it’s the secret to popular trends like “liquid hair”—yet its name remains elusive to most. So, what is this mysterious powerhouse ingredient whose products have bred such obsession, you ask? Lamellar water.

Although it may sound buzzy and new, lamellar water has actually been around for nearly four years. The rinse-out repairing and conditioning hair treatment was first introduced by Kérastase as an in-salon treatment called K Water, and it was patented by parent company L’Oréal Paris (meaning its technology can only appear in products made by L’Oréal’s brands). It promised to repair hair fibers and offer hair a glassy finish, making it an instant favorite among hairstylists and salon-goers alike.

More recently, however, lamellar water has been re-established as an at-home treatment, making it both more affordable and more accessible, so more users can experience its beloved effects. While it’s still considered relatively new, more and more products containing the hero ingredient are coming to market, each catering to different hair concerns and needs. Finding these products, let alone identifying which are best for you, can be a bit of a challenge, though, so we consulted the experts. Read on for everything you need to know about using lamellar water and where to find it (hint: it could be your local drugstore!).

What are the benefits of using lamellar water?

Lamellar water is known amongst hair stylists and experts are the secret to achieving the popular “liquid hair” look, but in addition to its aesthetic abilities, the ingredient can seriously enhance the health of hair. The water-based agent boasts the same ingredients as a traditional conditioning treatment but delivers them in a  gel structure that enables a lightweight texture.

“Lamellar water is so lightweight that it makes it easier to penetrate the hair cuticle, addressing damage to the hair on a deeper level,” explains Jonathan Colombini, a celebrity hairstylist and colorist for L’Oréal Paris. “It also allows the hair to maintain its natural volume and shape without the weigh-down caused by some traditional reparative masks or conditioners.”

How does it work?

Lamellar water typically comes in the form of a rinse-out hair treatment, though it can be left in for styling purposes. The lightweight ingredient is used to target and repair damage in hair, and deposits concentrated actives, like proteins and amino acids, to specific regions. But unlike other conditioning treatments, lamellar water has a gel structure, so it won’t leave behind a heavy, weighed-down feeling or any kind of moisture cast.

“Lamellar water can be incorporated easily into any hair routine,” says Krupa Koestline, a cosmetic chemist and founder of KKT Consultant. “It’s best to apply after cleansing, usually with shampoo, and then followed with a conditioner if necessary.” Like other conditioning treatments, lamellar water should be applied from the mid-lengths down, avoiding the scalp and focusing on the ends. Wait a few seconds, and then rinse out and proceed with the rest of your shower routine. Those with dry hair texture can use it alongside their standard conditioner, but Koestline notes that certain hair textures, including oil-prone, may want to forgo conditioner after the treatment.

What hair types does lamellar water work best on?

Lamellar water is one of those rare ingredients that really does work well on all hair types. “It’s great because it really is a lightweight treatment, so even thinner or more oily hair types can use it without worrying about the weigh-down of typical moisturizing treatments,” Colombini explains. That said, those with dry or brittle hair or significant hair damage will benefit most from using it.

Shop the best drugstore lameller water treatments

L’Oréal Paris Elvive Hyaluron + Plump Flash Hydration Wonder Water — $10.00

A favorite of Colombini’s, the Elvive Hyaluron + Plump promises shinier, hydrated hair without the heaviness. “It’s just like the original Wonder Water but also includes hyaluronic acid for extra hydration and softness,” the stylist says. This addition helps hair fibers retain moisture that lasts long-term.

Garnier Fructis Sleek & Shine Glass Hair Water — $9.00

Designed specifically to give a glassy finish, this water from Garnier Fructis transforms hair from frizzy or dry to ultra-smooth and shiny in just a few seconds. It’s free of parabens, silicones, and sulfates and won’t weigh hair down. Plus, its subtle green apple and melon scent will add some fruitiness to your shower and beyond.

Redken Extreme Bleach Recovery Lamellar Treatment — $28.00

This lamellar water treatment from Redken is ideal for color-treated hair but will help reverse hair damage of all kinds. The rinse-out conditioner acts as a liquid bandage and instantly increases softness, smoothness, and shine.

Not Your Mother’s Smooth Moves Instant Shine Lamellar Water Hair Rinse — $9.00

This lightweight, easy-to-use treatment from Not Your Mother’s doubles hair’s shine in just one use, leaving it brighter, softer, and smoother. And with a special FrizzLock Complex, the rinse helps instantly detangle even the toughest of knots.