Are you a morning person or a night owl?
Whatever your answer, we’re talking about your natural internal clock, or what scientists call your “circadian rhythm.”
You’ve probably heard about this lately, as researchers are learning more about it all the time. While they used to believe it affected mainly your sleep/wake cycle, new studies are showing it can affect a lot of other things too, including your weight, and your risk for disease like diabetes and heart disease—even cancer.
In fact, new findings show your circadian rhythm affects the health of your skin, too! That means if you’re not honoring your body clock and getting the sleep you need when you need it, your skin could suffer.
What is the Circadian Rhythm?
Think about a standard day in your life. There are probably certain times when you feel awake, and other times you tend to drag. For most people, energy drops to its lowest level in the middle of the night, like between 2:00 and 4:00 a.m., and rises again around breakfast time, then dips down after lunch, and rises again in the evening.
Individual energy peaks and valleys vary, however, depending on the person and his or her unique biological makeup. This is why some people naturally feel more awake at night and sleepy in the morning, while others get up rearing to go, but then fade quickly after dinner.
All this is controlled by a part of the brain called the hypothalamus, and is heavily impacted by your exposure to sunlight. When it’s light outside, the eyes take in that light, and the brain responds by sending the signal to release certain hormones in the body that trigger wakefulness. When it’s dark, the eyes register the darkness, and the brain responds by releasing different hormones related to sleeping.
Because of this natural response to light, our modern-day lifestyles have a way of messing up our circadian rhythms. Having lights on in the house late at night confuses the brain, and causes it to release more hormones related to wakefulness, which can make it hard for you to go to sleep. Staring at computers, tablets, and smartphones late at night has the same effect, as all these gadgets emit blue light. That blue light than causes the brain to release more waking hormones, causing sleep difficulties.
Other things like jet lag, daylight savings time shifts, and staying up later than usual can all affect your circadian rhythms, which in turn, affect not only how well you sleep, but many other things related to your health including hormone release, eating habits and cravings, digestion, metabolism, mood, cognitive function, and even the way the skin behaves.
How Your Circadian Rhythm Affects Skin
Recent research has discovered that the circadian clock regulates cell activity in the skin.
- Protection—the master body clock affects the skin’s ability to control sun-induced DNA damage in skin, and provides for either a weak or strong ability to protect from skin cancer
- Psoriasis—a disrupted circadian rhythm can make psoriasis symptoms worse
- Regeneration—the internal body clock regulates tissue metabolism and stem cell regeneration in the skin
- Aging—circadian rhythms affect the rate at which skin ages
- Sebum production—fluctuations in the circadian rhythm signal cells to either produce more sebum (skin oil) or less; typically, the skin produces more in the early afternoon, and less at night
- Moisture—the body clock affects how much moisture the skin holds onto
- Blood flow—the skin needs nutrients in the blood to look it’s best, and the body clock can affect how much blood is getting to skin cells
- Itch and irritation—research has suggested that these tend to become more noticeable at certain times of the day or night depending on circadian rhythms
- Temperature—changes in skin temperature are affected by the time of day
- Barrier function repair—that outer protective layer on the skin called the “barrier” protects from bacteria and viruses, while helping to hold onto moisture; circadian rhythms affect the repair of this barrier and when that repair occurs
Based on this research, we now know that anti-aging cells are most active at night—which confirms that applying our anti-aging serums at night is likely to produce the best results.
DNA repair of skin cells also occurs in the afternoon and evening, which suggests that if you get a sunburn in the morning, it will be a while before skin can go to work repairing it, potentially resulting in more lasting damage.
Skin seems to be more vulnerable to inflammation later in the day, too, which means that conditions like psoriasis, eczema, rosacea, and others may flare up more in the afternoon or evening.
We also know that when we mess up our circadian rhythms, the skin will look older. Studies have shown that lack of sleep, for example—which is either the result of a disrupted circadian rhythm, or a cause of it—results in increased fine lines and wrinkles and age spots. (Read our post, “Why Your Poor Night’s Sleep Could Make You Look Older.”)
Healthy Circadian-Rhythm Tips that Help Promote Youthful Skin
We can expect to learn more as scientists continue to research this area. In the meantime, there are things you can do to make sure that your circadian rhythm stays on track, which in turn, will help keep your skin looking its best.
- Go to bed and get up at the same time every day, even on weekends.
- Turn the lights down at least 90 minutes before bedtime.
- Remove all screens from your bedroom, including phones, tablets, laptops, and televisions.
- Stop using all technological gadgets at least an hour before bed.
- Create a before-bed routine that includes relaxing, quiet activities in dim light.
- Use your most potent anti-aging serums and moisturizers at night before bed.
- Never neglect washing your face before bed!
- If you’re suffering from insomnia, check with your doctor to find solutions.
- First thing in the morning, get some exposure to light. Open the blinds and turn on the light to help set your body clock to the proper wake time.
- Make sure you’re protecting your skin in the morning with sunscreen.
- Get outside in the afternoon for some exposure to the sun—it helps keep your clock on track, as well as helping you to produce vitamin D.
- Keep your bedroom cool, particularly if you tend to have irritated or itchy skin.
Have you noticed that disruptions in your daily routine affect your skin?
Matsui, M. S. (2016). Biological Rhythms in the Skin. Int J Mol Sci., 17(6), 801. doi:10.3390/ijms17060801
Plikus, M. V., Van Spyk, E. N., Pham, K., Geyfman, M., Kumar, V., Takahashi, J. S., & Andersen, B. (2015). The Circadian Clock in Skin. Journal of Biological Rhythms, 30(3), 163-182. doi:10.1177/0748730414563537