Your skin’s stem cells’ activity follows your circadian rhythms. During daylight hours, they switch on genes that defend against UV light and pollution. The morning antioxidant boost is vital for protection from the free radicals that will start to accumulate as soon as you step out into the light. At night, your cells don’t have to be on the defensive, and instead focus on producing healthy cells to replace the damaged ones. The peak for nighttime repairs is between 10 p.m. and midnight. The key to maintaining this balance? Stick to a solid sleep schedule.


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