Dry shampoo is often hyped up to be a super convenient holy grail for refreshing oily hair—fast. In theory, a few spritzes should hide the fact that you skipped a wash (or three). But as someone with perpetually greasy roots, I’ve mostly been let down by these alleged miracle workers. That is, until I tried one simple—but game-changing—dry shampoo hack I saw on TikTok.
In a video with more than 4 million views, dermatologist Lindsey Zubritsky, MD, shared a common mistake that may explain why so many of us haven’t experienced the grease-fighting results we were promised. It turns out, when you use dry shampoo can make all the difference: “If you start using this at nighttime, it will change the game to soak up oil all night long,” Dr. Zubritsky says in the video.
It might sound a little weird to apply a styling treatment before bed. But according to the two dermatologists we spoke with, it actually makes total sense. For a quick refresher (pun intended), dry shampoos are packed with super absorbent ingredients like starches, clay, and silica. “They sop up oil by binding to the sebum sitting on the scalp,” Marisa Garshick, MD, a board-certified dermatologist in New York City, tells SELF. “Starches and clays, in particular, are also porous, which means they’re great at trapping and holding onto dirt and preventing your hair from looking greasy.”
While these actives only need a few minutes to kick in, leaving them to do their thing overnight makes them work even better. “Dry shampoo becomes more effective with time, so if you let it sit while you sleep, it has longer to bind to and absorb all the oils and dirt on your scalp,” Ife Rodney, MD, board-certified dermatologist and founding director of Eternal Dermatology Aesthetics in Fulton, Maryland, tells SELF. Plus, one reason your roots may feel extra gross in the morning is that your scalp continues to produce sebum and sweat as you sleep, Dr. Rodney explains. So dry shampoo can soak up that buildup all night long, leaving you with hair that looks—and feels—fresh as soon as you wake up.
For the best results, both derms recommend shaking your dry shampoo bottle and spraying it about six to eight inches from your head (or with a powder, dabbing it directly onto your scalp.) And the key is to let it work its magic overnight—without brushing it out. By styling or massaging too soon, you run the risk of wiping off the product before it’s had a chance to settle in and do its job, Dr. Rodney warns. (We get it though—these formulas can sometimes leave your hair feeling uncomfortably stiff. So if that’s the case, Dr. Garshick suggests waiting at least five minutes before you start finger combing.)
