Chances are, upon hearing the words hyaluronic acid (HA) [1], your mind will go straight to a face cream [2] or a serum. It makes sense, as the buzzy ingredient has long been known for its ability to pull moisture [3] from its surroundings and hold up to 1000 times its weight in water. It saves dry skin [4] while giving it an added radiance — but what happens when it's swirled into your hair care?

Brands are injecting hyaluronic acid into the formulas of every step of your haircare routine because it is a powerful moisturising agent regardless of where you decide to smear it. Cosmetic chemist Ginger King told POPSUGAR that the best way to apply it to hair is in the form of a conditioner (preferably a leave-in). "Conditioners have cationic charges, which helps to retain the moisture," she said. She explained that it should be applied at least once a week, or whenever your hair is feeling dry.

King does have one caveat: "Hair is dead." She explained that while HA still helps with locking in moisture, it's not as effective at making your hair shine as other ingredients. She also said that HA is most beneficial when applied directly to the scalp. "The scalp [is] skin so when you keep it moisturised, it makes hair grow better like fertilizer."

Beauty brands aren't the only part of the industry using HA. Salons are offering treatments with the ingredient as well. Hairstylist Nunzio Saviano offers a hyaluronic-acid-infused leave-in treatment at his New York City-based salon that he recommends to his clients with colour-treated hair. Post-treatment, he says, clients are left with hair that feels significantly softer, and he provides clients with a one-step HA hair serum that they can use to keep the effects going.

Ahead, see five hair products that contain the ingredient.

IGK Thirsty Girl Shampoo and Conditioner

IGK Thirsty Girl Collection [5] ($25) includes a shampoo and conditioner with HA for softer, smoother hair.

David Mallett Fresh Eau de Concombre Menu Materiae Cart

Spritzing the multitasking David Mallett Fresh Eau de Concombre [6] ($48) will give dry skin and hair the burst of moisture it needs.

NatureLab Shine Oil Mist

NatureLab Shine Oil Mist [7] ($16) blends HA with plant oils and butters for soft, shiny hair.

Oribe Power Drops Damage Repair Booster

Oribe Power Drops Damage Repair Booster [8] ($58) is a potent mix of HA, fatty acids, biotin, and vitamins for smoother, stronger hair.

Living Proof Restore Dry Scalp Treatment

Living Proof Restore Dry Scalp Treatment [9] ($32) uses HA and vitamin B3 to sooth and restore health to dry, flaking scalps.