I’m reading more frequently that our current tendency to be staring at screens and living in our unnatural always-lit environment is really messing up our internal circadian clocks. In a natural world, the human circadian cycle adapts to seasonal changes in the light-dark cycle. But staring at screens (TV, computer, phone), especially in the hours prior to trying to sleep, is harmful to our internal clock’s synchronization and the way our brain prepares for sleep. And sleeping in for an extra hour doesn’t really help.
You’re finally relaxing on a winter night after a tough day spent in artificial light when you barely made it outside. You walked to your car or the mass transit in early morning darkness. You left work and it was already getting dark. At home, you were bathed in a brightly lit home. You watch your big screen TV and have your tablet on your lap.
You’re really messing up your internal clock.
Can we reset our internal clock by avoiding artificial lights at night for a few days and turning off those screens? That is tough to do in most modern settings. No screens and no artificial lighting? You can’t even do that on most vacations.
Some people try using meditation or other techniques to control stress ot to “defrag” your brain. Scientists have known for quite a while now that light is the most powerful cue for shifting the phase or resetting the time of the circadian clock. They have been cautioning against using light-emitting devices before bedtime because they emit “short-wavelength-enriched” light – light with a higher concentration of blue light than natural light contains. Blue light affects levels of the sleep-inducing hormone melatonin more than any other wavelength.
In a study published in Current Biology, the authors describe a series of experiments where people were sent out camping to reset their biological clocks. The paper is titled “Circadian Entrainment to the Natural Light-Dark Cycle across Seasons and the Weekend” but in simpler terms it tested campers who spent a week and some who spent a weekend in a tech-free and only natural lighting setting. This study compared them with a control group that stayed at home to live their normal life. The scientists tracked sleep and circadian rhythms by measuring their levels of the hormone melatonin, which regulates wakefulness and sleep.
Melatonin levels are key. We know that melatonin is present at low levels during the day, begins being released a few hours before bedtime, and peaking in the middle of the night. Those levels fall and then we wake up. Unfortunately, in our current living environment, melatonin levels don’t fall back down for a few hours after we wake up. To your brain, you should still be sleeping for several hours. It’s like jet lag.
But that week-long camping trip seems to have reset the participants’ internal clock. Living in a world lit by light bulbs and screens is very different from one of sunlight and moonlight.
I try year round to get out to at least my backyard as soon as I make my morning coffee to get at least 15 minutes of sunlight. Of course, sometimes there is not much sunlight and in winter here it’s not as pleasant to step out in your pajamas when it’s 20 degrees and there’s snow on the deck. Natural light, particularly morning sunshine, which is enriched with blue light, has a very powerful influence on setting internal clocks to daytime and waking up.
Of course, a week of real camping (not a spa week or vacation at a resort) is not possible or even desirable to everyone. Can you create a natural light-dark cycle for a weekend? It means turning off the screens and turning off all of the artificial lights.
The study found that over 60% of the shift can happen over a weekend. Assuming the weekend is Friday, Saturday and Sunday nights, that would give you a 20% recovery per night. Add 2 more nights to get 100% recovery? Five nights to reset your clock.
Of course, we’d like an easier path.
One alternate path reminds me of other “detox cures” that are quite popular. For example, I read an article on how to reverse some liver damage. In brief, it suggests that you avoid alcohol and processed foods, exercise more, lose 10% of your weight, take some milk thistle and maybe some Vitamin E. That sounds like good general health advice, but other than taking some supplements, it also sounds like a tough regimen for most of us to follow.
That is why a lot of people have decided to try taking melatonin supplements. It’s easy, and it sounds logical. You lack the melatonin to induce sleep, so you add some artificially. I tried resrtting my circadian rhythms using melatonin about a year ago. I read about what the levels are supposed to be. I made a schedule of when I would take the melatonin and when I would go to sleep. I adhered to the schedule – for two weeks.
The experiment did seem to work. I felt like I was falling asleep faster and staying asleep better. I didn’t do anything with light. I suspect that part of the improvement came from sticking to a regular sleep schedule. I was going to bed at 11 pm and waking up at 7 am for a solid 8 hours. But I just couldn’t keep to the schedule. I continued taking the melatonin until the bottle was empty, but I was going to bed at 1 or 2 am some nights and waking up at 6, 8 or even 9 am. That’s not how to do it.
People also try using artificial lights that mimic the spectrum and the intensity of natural light, but that can be costly. It is one of the therapies for Seasonal Affective Disorder (SAD) that hits people as the “winter blues.”
I’ll be taking a week away from the winter blues soon and I will try, as best I can, to break from the screens and live by the sunlight and moonlight.