Sleep and circadian rhythms

Sleep and circadian rhythms

You need enough sleep to be healthy and function optimally. No study has shown that not sleeping enough causes acne, but I’ve heard from many people who say their acne went away after they started sleeping more. Long-term sleep deprivation is also linked to insulin resistance and a higher risk of diabetes, heart disease, and other health problems.

According to the National Sleep Foundation, most adults need 7 to 9 hours of sleep a day. How do you know if you get enough sleep? Do you:

  • Have difficulties waking up in the morning?
  • Feel like you need more sleep?
  • Feel drowsy during the day?
  • Feel moody or easily irritated?
  • Have difficulties focusing and feel like you aren’t as productive as you could be?
  • Look tired?

Then you might need to sleep more.

And while we are at it, it’s best to go to bed at a reasonable hour (say 10 to 11 pm) and wake up early.

I’m sure you are familiar with circadian rhythms, or the body clock. Most life organizes itself around the light-dark cycle, including humans. Circadian rhythms refer to different cycles in the body that govern various functions. From Wikipedia: “There are clear patterns of brain wave activity, hormone production, cell regeneration and other biological activities linked to this daily cycle.”

There’s good evidence to show that messing up with your body clock, i.e. misaligning it from the natural light-dark cycle, is bad for your health. For example, strokes and heart attacks are 8 to 10% more common in the two days following daylight saving time shift (source). Similarly, a 2015 review concluded that not getting enough sleep and circadian misalignment can cause insulin resistance and increase your risk of obesity and diabetes.

But it’s not just what time you go to bed. Things known to affect your body clocks include:

  • The light/dark cycle and the wavelength of the light
  • The time you fall asleep and wake up
  • Exercise
  • Eating
  • Stress

While the science is anything but settled, there’s evidence to show that aligning your behavior with our natural rhythms is good for you. For example, in the meal timing page, I talked about a study where women with PCOS were divided into two groups. One group was asked to eat a heavy breakfast and light dinner, and the other group was asked to eat a light breakfast and a heavy dinner. Otherwise, both groups had identical diets. After 90 days, there was a massive improvement in all acne-relevant parameters in the group that had a heavy breakfast and light dinner. Usually, getting similar benefits requires a combination of prescription drugs and a rigorous exercise program.

Here’s what you can do to fit your behavior into our natural rhythms:

  • Go to bed and wake up at the same time every day. It’s not a good idea to sleep in during the weekend.
  • Try to get to sleep by 11 pm. There are genetic differences in people, and if you know you are a night owl, it’s not a good idea to force yourself to go to bed too early (source). This article outlines how to find the ideal time to go to sleep for yourself.
  • Avoid exercising 3 to 4 hours before bedtime.
  • Try not to use smartphones, tablets, computers or other devices with an LED screen in the evening. These devices emit blue light that’s been shown to disrupt circadian rhythms. I wrote a blog post about this earlier. Kindle, e-readers, and other devices that don’t emit light won’t cause problems. If you need to use light emitting devices, consider apps, like f.lux, that adjust the spectrum of the light and reduce blue light in the evenings. You can also find films and screen protectors that filter out blue light, but I don’t know how effective they are.
  • Get most of your calories in early and keep dinner as light as possible.

About Me

Hi, I am Acne Einstein(a.k.a. Seppo Puusa). I'm a bit of a science nerd who is also passionate about health. I enjoy digging through medical journals for acne treatment gems I can share here. You can read more about my journey through acne and how I eventually ended up creating this.