Why Your Skin’s Circadian Rhythm Is The Key To A Healthy Complexion

If you find yourself tossing and turning throughout the night, the habit of scrolling through TikTok on your phone before hitting the lights could be to blame. While it’s been scientifically proven that blue light emitted from phones can throw off the body’s natural clock and mess up its sleep cycle, it turns out the skin has its own circadian rhythm that requires the same consideration in order to maintain a healthy complexion.

Kim Walls, co-founder and CEO of Furtuna Skin, says our skin enters “protect mode” during daylight hours as it instinctively needs to fight off environmental stressors like radiation and air pollution. On the flip side, it knows to shift into “repair mode” in the evening, as rejuvenation happens during sleep. “Most of the body's repair systems are nocturnal and require deep rest in order to be fulfilled,” says Kristina Holey, skincare expert and co-founder of Marie Veronique + Kristina Holey. “When deprived of proper rest and repair time, the skin starts to complain in ways that are as noticeable to us as yawning — a dull complexion, more wrinkles around the eyes, blotchiness, and so on.”

Ahead, TZR speaks to skin experts about the function of the skin’s circadian rhythm and how timing is key when it comes to maintaining skin health.

What Is The Skin’s Circadian Rhythm?

Just like our body, Walls says our skin has its own 24-hour biological clock that’s ruled by the earth's day and night cycles. “The skin circadian rhythm matters because when the skin's biological clock is disrupted, it can cause dehydration, breakouts, diminished radiance, and more pronounced dark spots, lines, wrinkles, and sagging,” she says. “To avoid this, our skin needs to be continuously recalibrated to maintain a synchronized clock and a glowing appearance from dawn to dusk.”

Luckily, staying in harmony with Mother Nature really isn’t that hard to do. With research showing there is a circadian rhythm to the production and metabolism in our connective tissue, as well as a time to “reset and repair”, it’s easy to parse out what products to use and when to use them. Renée Rouleau, skin expert and celebrity aesthetician, sums it up: “By understanding circadian rhythm, you’re able to use the right skin care products at the right time of day, which can really optimize your routine and best support your skin.”

How Does The Circadian Rhythm Impact Skin Health?

Holey explains that epidermal integrity (maintaining bouncy, wrinkle-free skin) is governed by collagen and elastin fibers which form the supporting grid found in the dermis (called the extracellular matrix). Multiple factors influence collagen turnover and production that occurs at night while we sleep, some of which we can control. “For example, we can deliver the nutrients required like vitamins A and C to the skin tissue to make collagen, and can modify our lifestyle habits to make sure we get enough rest,” she says.

Stephen de Heinrich, Co-Founder of Omorovicza agrees, adding that skin barrier permeability is higher during the night so there is increased transepidermal water loss and potential for more dryness and irritation. “Increased blood flow in the evening and overnight is linked to a higher chance of inflammation within the skin,” he says. “Our circadian rhythm regulates the expression of cortisol, the primary stress hormone, which if not properly balanced can lead to premature aging including the formation of fine lines and wrinkles and increased dryness.” When the circadian rhythm is disrupted by things like lack of sleep, diet, stress, UV exposure, and hormonal fluctuations, it can lead to premature aging due to elevated cortisol levels or decreased melatonin.

Which Skin Care Ingredients To Use Day & Night

Rouleau says that daytime is for antioxidants and sunscreen, point-blank. “UV, pollution, and free radicals are hitting your skin all day, so it’s important to use ingredients that protect, as too much sun exposure can actually interfere with your skin’s nighttime repair process.” She goes on to say that since your skin already produces antioxidants during the day, giving it an extra topical boost with antioxidant-rich vitamins will help prevent further damage.

However, nighttime is when products can soak in deeper while the skin is in repair mode, so she suggests periodically starting off with a gentle exfoliator. “Your skin cells grow and divide at a higher rate at night so using products that exfoliate and help regenerate skin is a great move,” she says. She likes AHAs or BHAs as a great before-bed ritual as they dissolve dead skin cells, allowing follow-up actives in products to penetrate deeper.

As far as nighttime active ingredients go, Walls draws parallels with food’s ability to improve energy and metabolism when strategically eaten. “At night, look for active ingredients like adaptogens, ashwagandha, bakuchiol, and retinol to accelerate the skin’s renewal process while it’s in repair mode,” she says. “Additionally, ingredients like olive oil, hyaluronic acid, and ceramides will restore moisture during the skin’s peak transdermal water loss phase, which is essential for a healthy skin microbiome.”

Additionally, you should pay attention to what time you start your nighttime skin care routine. “We used to think the skin’s repair processes only occurred at night during sleep but it actually kicks in as soon as the sun goes down,” Rouleau says. “Because your skin has its own circadian rhythm, the loss of daylight signals that it’s time to start moving into repair mode, even if you’ve haven’t gone to bed yet.” To optimize product results, she suggests doing your nighttime skincare routine earlier in the evening rather than waiting until right before your head hits the pillow.

In the end, a lack of sleep may age us faster than anything else. “Among many other health risks, inadequate sleep is known to raise cortisol levels which increases inflammation, disrupts the skin’s microbiome, breaks down major proteins, and causes skin sagging,” Walls says. So in the end, if you want healthy skin, prioritizing sleep and creating a sleep routine is just as important as your morning and nighttime skin care routines.

Below, a few products that work in tandem with the skin’s circadian rhythm to incorporate into your routine.

Skin Circadian Rhythm-Friendly Products

Morning

Nighttime