Hacking Better Sleep – Light, Screens, and Circadian Rhythms


If you’ve ever suffered a power outage that lasted into the night, you’ve probably found yourself going to bed earlier than usual. You may have thought it had something to do with there being less to do, without TV, computers, or electric lights. However, there’s a greater chance that your body simply knew it was time to go to bed due to the prevalence of darkness. Put a person in darkness, and the brain will often decide it’s a good time to go sleep.

Humans are naturally diurnal; we wake on feeling the sunlight entering our rooms and get sleepy when the sun goes down. The luxury of being able to stay up late into the night to finish work (and play) is a fairly recent development in our evolutionary history. Humans being daytime mammals isn’t just an observation—but has been proven by science, from analyzing the chemical and hormone levels in the blood and how they respond to light entering through the eyes. Show me a person who claims to be “nocturnal” and I’ll show you a person who has confused his natural circadian rhythms (and is likely operating on a sleep deficit).

One of the things we’ve learned is that the brain releases a hormone called melatonin to help us get sleepy when the day shifts into night. This discovery has led to the synthesis of melatonin for sale as a natural sleep enhancer for those of us who have trouble falling asleep. But the truth is that most of us don’t need melatonin supplements to make us sleepy. We just need good sleep hygiene.

A working awareness of how routines and light affect the body’s circadian rhythms can help you make choices that help you fall asleep without having to take a pill that alters your natural chemistry. Scientific studies have found that light, especially blue light (which closely mimics daylight) is the worst for transitioning to bed time. When photoreceptors in the eyes sense the presence of blue light, it inhibits the release of melatonin and can keep your brain alert, even when your body is starving for sleep.

One obvious piece of advice we can all take away from this tidbit is that no one should be looking at a screen at bedtime. This can be a hard pill to swallow, as many of us have replaced reading from books and magazines (which don’t produce blue light) with reading from a screen. Most of us get our news from a screen held within a foot or two of the face. Watching a screen on the other side of the room (TV) may be a bit better, but it still isn’t as soporific as the old bedtime habit of low-light book-reading. A better choice is to turn off the lights entirely and read from your screen in the morning–after you’ve slept!

Key Take-Aways

Current recommendations say that neither children or adults should be staring at a screen within two hours of bedtime. This means computers, video games, phones, etc. If you need to set an alarm or check your email in bed, change your screen to a night-time mode that reduces blue light. Many devices have these settings and it can be to your benefit to use them.

Overall, darkness helps your body fall asleep. Keep lighting low and screens turned off when it’s time to turn in. There are very few people who can fall asleep easily just because they decide it’s bedtime. The body needs some convincing. Avoiding caffeine, exercise, and blue-light-bearing screens are great ways to get your body headed in the right direction and listening to its natural impulses.

About the Author: Dr. Mickiewicz owns a private practice in Sacramento and lectures across the nation on TMD treatments. He is a diplomate of the American Academy of Pain Management and holds membership in many professional associations for dentistry, sleep medicine, and TMD. In addition, Dr. Mick, as his patients call him, founded Pacific Orofacial Pain Consultants, a team of experts in various disciplines, who tackle the issue of TMD pain and treatment, to help sufferers find relief from chronic pain. To talk with Dr. Mick, call his Sacramento dental office at 916-469-9178.

Leave a Reply