Just as your body is governed by a circadian rhythm, so is your skin. As day turns to night, this internal clock lets the cells in your body know that a shift is occurring, triggering a series of important changes that allow every major organ to function at full capacity.

“Think of skin cells as tiny, busy little factories. They only get so much energy, so they have to prioritize what they do,” explains Dr. Colette Haydon, dermo-pharmacist and founder of beauty brand Lixirskin. “It’s very logical: in the daytime, when skin is exposed to many aggressors, it goes into protection mode. At night, when there are fewer aggressors, it can prioritize other things, and goes into repair mode.” In many ways, we can relate. You work hard by day, juggling the many demands that come your way, and, come nightfall, it’s all about relaxing, recuperating and making sure you’re ready for the following day.

So, your skincare routine is ultimately your chance to work in tandem with those skin cells to give them the support they need. But how exactly is your skin changing from day to night? And does a modern skincare regime support these in-built processes?

“All day long our skin is fighting environmental aggressors, pollution, oxidative stressors, temperature changes and more,” says New York-based dermatologist Dendy Engelman. “So, our morning skincare routine is super-important to provide our skin with the tools it needs to combat these assailants.”

In essence, it’s about working in harmony with your skin, not against it. If your cells are in ‘protect mode’ by day, producing lipids to strengthen the skin barrier, it makes sense to tailor your routine accordingly. What does that mean? You should be reaching for antioxidant-rich serums, barrier-strengthening fatty acids and free-radical-fighting vitamin-C skincare. Anything that compromises the skin barrier is better saved for night. So, while a peel might instantly boost your glow and help makeup glide on smoothly, you’re ultimately working against your skin. “By using acid [in the morning], you’re unnecessarily sensitizing your skin when it is trying to protect, and making it more vulnerable to UV rays,” says Haydon.

Your morning cleansing routine needs consideration, too, with only the gentlest of refreshes required after your skin’s busy night of repair. “Start your day with a gentle, hydrating and non-stripping cleanser that strengthens and preserves the epidermis, as well as removing oil, debris and bacteria that have accumulated overnight,” says Dr. Anita Sturnham, founder of skincare brand Decree, whose Light Cleanse is designed specifically for morning use. And you shouldn’t need reminding that a layer of broad-spectrum SPF is the best daytime skin protection of all.

Just as slipping into lavender-scented sheets can enhance your sleep quality, a carefully thought-out skincare edit can turbo-charge your skin’s nightly revitalizing rituals. “Ever notice how great your skin looks after a good night’s sleep? This is because skin regeneration is at its height overnight,” says Engelman. And with your skin turning its attention to the synthesis of proteins like collagen and elastin, retinol makes a natural bedfellow.

“A retinol, like Lixirskin’s Night Switch Retinol 1%, boosts the production of protein to help with skin density and wrinkles, and that’s something that already happens at night,” says Haydon. “You’ll benefit a lot more from retinol when it’s applied at the right time for your skin to be making proteins – it is more receptive because the skin is in repair mode already. I always say: ask the skin to do one thing at a time and do it well.” And for the same reason, don’t be swayed by products claiming they can do it all. “The skin is receiving too many messages and can’t benefit from it all,” says Haydon. “For example, vitamin-C skincare at night isn’t a problem, but it’s so much more beneficial in the daytime, when your skin is already in protect mode. Support your skin in what it’s already doing.”

As day turns to night, your skin moves away from producing lipids, meaning your complexion might feel drier overnight. “At night, the PH of our skin rises, the epidermal barriers weaken, blood flow increases, and sebum production reduces,” explains Sturnham. “Our skincare strategy needs to support these cyclical changes.” This is when to look to those ultra-hydrating products to really lock in moisture while you sleep, as well as counteracting any dryness triggered by retinol use.

And finally, when it comes to timings, look to the light. While our ‘clock genes’ are generally understood to have skin at its regenerative best between 10pm and 2am, the sleep hormone melatonin is triggered by a loss of daylight (which explains why we just want to hibernate in winter). Research by Estée Lauder has shown that blue light (found in sunlight and emitted by digital devices such as phones) plays a role, too, throwing skin’s natural night-time rhythm out of sync. To get the most out of your skin’s cycle, consider doing your nightly skincare routine a little earlier, to cash in on those extra hours before bed. And have you ever had a better reason to make your phone out of bounds come nightfall?

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