To be perfectly honest, we had no idea. Until we started chatting to New York dermatologist Dr Gee Young Bae (who happens to be Kiehl's go-to derm, no less) and French thermal water brand Avene's brand manager Julie Dejean, who cleared up the whole 'cosmetic waters' mystery - and made us wish we'd jumped on the bandwagon sooner.
"Cosmetic waters appeal because they're gentle yet very effective and can be used on a variety of skin types," Dejean tells us. "They're also incredibly practical - some cosmetic waters can perform several skincare functions at once, such as removing make-up and cleansing in the case of micellar lotion, or calming and softening in the case of facial mists."
Confused by all the new terminology flooding the skincare shelves? That's because cosmetic waters come in different guises (just as there's saltwater, freshwater, rainwater - you get the picture). But each one is a valued step in the Korean beauty girl's intensive skincare regimen. "My patients in Asia often apply cosmetic waters as a mist or serum," says Dr Bae. "They're widely appreciated for their ability to improve skin's texture and hydration, resulting in better absorption and a synergistic effect with following steps in a skincare routine." But just which should you be using - micellar, toner, mist, essence or the lot? Read on to find out.
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1. Micellar water
"Micellar waters consist of a 3-in-1 no-rinse formula that cleanses, tones and removes make-up up simultaneously," says Dejean. "All skin types can use cosmetic waters, however skin that tends to be sensitive benefits the most as cosmetic waters are very gentle, particularly if you opt for a natural option such as Avene's Micellar Lotion or Thermal Spring Water." In other words, they're the perfect lazy girl's option when you've had a big night and make-up removal seems too hard. They're also a dream for double cleansers - apply after your first wash to get rid of any remaining grit. Added bonus: the formulas are so gentle there's no need to worry about stripping your skin.
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We know you probably had a bad experience with stinging, astringent toner in high school, but hear us out: the latest crop of toners is worth the extra step each night, especially if you're the type who already uses a lot of product. The role of a toner is to clear the skin of excess oil and balance its pH levels. "Toners can be of different types: hydrating, soothing, astringent," says Dejean. Just steer clear of the outdated alcohol-based formulations responsible for drying you out last decade - instead, look for soothing ingredients such as Aloe Vera, apricot kernel oil or calendula.
Essences are one of the latest beauty buzz words, formulated to help you get the most out of the active ingredients in the high-tech serums and moisturisers we're all using. Unlike toners, their job is to provide a surge of moisture to the skin. "The watery texture of treatment essences instantly hydrates the skin and smoothes skin's texture," says Dr Bae. "Compared with a richer texture, they deliver moisture faster and have a higher skin-boosting effect by increasing the absorption of subsequent treatments." Try Kiehl's new Iris Extract Activating Treatment Essence, $48, a triple threat that encourages skin cell renewal and replenishes moisture thanks to Lipo Hydroxy Acid, Iris Florentina root extract and sodium hyaluronate. Apply essences after cleansing and toning by pouring a few drops into the palms of your hands and patting onto your face, neck and chest. They feel extra dreamy when applied after a clarifying masque or peel. Or, take this dermatologist-approved tip: "For concentrated moisturising care, soak a sheet mask in a water essence and put it on your face for 10 minutes," advises Dr Bae.
4. Facial mists
The main difference with a mist is all in the application - they often contain similar ingredients as hydrating toners and essences, but are packaged in handy sprays that make them perfect for summer - especially if you keep them in the fridge. "A facial mist soothes and softens the skin," says Dejean. "You can carry it with you to apply anywhere for an instant hydration boost." Try decanting your preferred cosmetic water into a spray bottle for a tailor-maid refresher.