Your quality of ZZZs overall can impact your skin, too. Poor sleep can take a toll on your skin, says board-certified dermatologist Dr. Hadley King, M.D., which can lead to increased stress hormones, worsening inflammatory skin conditions like rosacea, acne, and eczema — all the more reason to get the recommended 6 to 8 hours of rest.
For the full low-down on what happens to your skin when you sleep — including how to reap the most beauty sleep benefits — here’s what to know.
1. Your Skin Can Retain Fluid
Since you’re horizontal in your bed when you sleep, King says your fluid balance — aka the liquid hydration within your body — recalibrates. In other words, when you’re upright during the day, your fluid is better circulating throughout your body, but when you’re lying in bed, it can make its way to your face. “That’s one reason why we get puffier in our face, particularly around the eyes, overnight,” she says. Her remedy? Apply eye creams with caffeine. “Caffeine constricts the blood vessels so you’ll get less fluid accumulating there,” she says.
2. Your Hormone Levels Fluctuate
King says that getting enough sleep is critical for the healing and repair of damaged tissues. “During sleep our bodies produce fewer stress hormones and more growth hormones and body-repairing hormones, allowing damaged cells to be repaired,” she says. If you don’t get enough sleep, your body can increase your stress hormones, which can lead to flare-ups of inflammatory skin conditions like acne and psoriasis, she says. Plus, without deeper phases of sleep, cell turnover cannot occur, which results in more noticeable signs of aging, King says (studies have also shown that sleep deprivation can increase fine lines and reduce elasticity).
3. Your Collagen Production Is Affected
Though collagen production doesn’t just happen when you sleep, nighttime is the best time to take advantage of the process, says Waldorf. “During the day, there’s more going on [in the outdoor environment like exposure to UV rays and pollution] that could damage it,” she says. When you sleep, take advantage of using retinoids, antioxidant serums, and bakuchiol (a plant-based alternative to retinol) to promote collagen in an environment where your skin isn’t threatened by outdoor elements. Plus, ingredients like retinol make your skin more sensitive to the sun, says King, so they’re best used at night.
4. Your Pillowcase Can Cause Lines
If you’re a side-sleeper, listen up. “One big downside [that happens] while you’re sleeping is that your face is often pressed into a pillow,” says Waldorf. “We get things called sleep lines, and the sleep lines are from pressure.” You could sleep on your back to avoid this, but some people have trouble holding one position all night. For your best skin protection, Waldorf recommends using silk or silk-like pillowcases as they cut down on the friction between your face and the case. She also suggests using pillows made to protect skin from creases, including those with dips or holes on the side, that don’t allow your skin to get smushed.
5. Your Skin Loses Moisture
When you’re snoozing, you can experience transepidermal water loss, says Dr. Daniel Sugai, M.D., a Seattle-based dermatologist, which basically means your skin loses moisture. This is more drastic during the wintertime in a dehumidified environment. His tip? It’s essential to seal moisture into your skin, so be sure to use a moisturizer. Sugai recommends an occlusive like Vaseline or Aquaphor, but King says you can use any moisturizer that contain humectants to hydrate and emollients to support the skin barrier.