Ever noticed you sleep better after you’ve been camping? It’s not just because you’ve been exerting energy hiking and backpacking. It’s also about exposure to natural light.
For most of our time on the planet, human beings went to sleep shortly after the sun went down and got up with the sunrise. Candles and oil lamps pushed bedtime back a little, but for the most part, if the sun wasn’t up, we were sleeping.
Then along came gas lights, and the electric light bulb, and laptops, and televisions, and suddenly the night was ablaze with so much artificial light city dwellers have difficulty seeing the stars. We beat back the darkness, replacing it with primetime TV and well-lit streets. Both of these admirable achievements came with a cost.
Artificial light forced back humanity’s bedtime, and in doing so sparked epidemics of sleep deprivation and insomnia. Now Kenneth Wright, professor of integrative physiology at the University of Colorado, Boulder, believes we have a simple way to reset our body’s sleep schedule: camping.
Melatonin and Sleep
The circadian rhythm is the body’s internal clock, and affects when we produce the hormone melatonin. Melatonin makes people feel tired, with levels of the hormone rising a few hours before we go to sleep. Melatonin also lowers the body’s core temperature, making it easier to fall asleep. When we wake up, melatonin levels quickly drop.
Wright says exposure to artificial light messes up melatonin production, with levels staying high for up to two hours after we wake up. So we feel tired in the morning and stay up later at night, putting the brain and body into a chronic state of low-level jet lag.
Wright believed avoiding artificial light at night and exposing the eyes to natural morning light could reset our out-of-sync circadian rhythms. He tested this hypothesis by sending a group of test subjects camping in the Rockies for a week.
After seven days of camping, test subjects’ sleep schedules shifted. They went to sleep about two hours earlier and woke up two hours earlier than they did before the camping trip, and their melatonin levels dropped quickly on awakening. Exposure to natural light—and avoidance of artificial light—reset their internal clocks.
As if you needed another excuse to go camping, right?