You may choose to skip a morning cleanse, especially if your skin runs dry—but a nightly wash is nonnegotiable. “If you only want to [cleanse] once a day, do it at night so you can take all the pollution off before you go to sleep,” board-certified dermatologist Jeanine Downie, M.D., says regarding how often you should wash your face.
You see, pollutants and daily grime build up on your skin as the day goes on, which can contribute to oxidative stress, dull, crepey skin, and fine lines if you don’t cleanse before bed. “Pollution can subject the skin to free radicals, which can contribute to the breakdown of collagen and elastin and lead to aging of the skin, so it’s important to cleanse the skin to avoid these effects,” adds board-certified dermatologist Hadley King, M.D.
And if you wear makeup, that makes it even more important to give your skin a good scrub. Frequently sleeping in your makeup can not only cause clogged pores but even lead to premature skin aging.