The writer lived underground for 10 days to study sleep, happiness, and health

In an effort to better understand how factors like meal times and the amount of sunlight affect our ability to feel rested, happy, and balanced, Lynn Peeples descended 50 feet underground for 10 days.

Peeples, science journalist and author of “Internal clock: living in sync with our circadian rhythms“, found an Airbnb in Arkansas which was once a bunker during the Cold War.

“This guy bought an old nuclear missile bunker from the government and rigged it up,” she said in the episode “Every day is better with Leia Smart“podcast.

In her words, there was “no daylight” in the bunker. Peeples also got permission from the Airbnb host to tape all the clocks on the digital devices with black tape so she couldn’t tell what time it was.

There was a dim red light in the bunker. “We know that red is a wavelength of light has the least effect on our circadian rhythms“, she said.

For her book, Peeples wanted to explore what would happen to her internal clock “if I cut myself off from the signals they need to tell time.”

During her stay, Peeples documented her experiences with voice recordings, with a plan to use time stamps to see how closely she followed her regular schedule — like when she ate breakfast or when she went to bed.

“For the first couple of days it was a miracle because later on I could look at the timestamps from the voice recordings I made and I lived a 24-hour day pretty accurately,” she said. “Our clocks inside us are actually telling pretty good time.”

But about halfway through the experience, Peeples began to feel “really out of it,” which she likened to a sharp jet lag.

“In the worst case, I was completely upside down. I lived my day when everyone else was sleeping above the ground. So, I was on vacation for almost 12 hours,” she said. “I felt the effects of it.”

Peeples began to experience moodiness, “feeling hot and cold” and feeling hungry when her internal clock was not well synchronized with her normal schedule. She also noticed that her thinking was more clouded and she was more clumsy than usual.

“Not that it wasn’t expected, but to really feel it was very profound.”

If your circadian rhythm is out of sync, you may experience fatigue, insomnia, headaches, or even depression, according to Cleveland Clinic. The results of the Peeples experiment further confirm what research has shown about how certain factors, such as exposure to sunlight, can affect the circadian rhythm.

“To maintain this calibration, it is approx get enough bright light, especially in the morning” Peoples said.

“For the first hour or two after waking up, if you can expose your eyes to bright daylight,” you’re in good shape.

Go for a 15-minute walk in the morning and “stay as close to the window as possible during the day,” she suggested. at night dim the lights in your home as you approach bedtime prepare your body for sleep.

Aligning your lifestyle with the 24-hour cycle is vital to your body’s functions, including processing food properly and “priming our immune system” to fight off certain pathogens. It’s the best way to “keep all those body systems working at their best by doing the right things at the right times.” she said.

Peeples also presented a list of things that can disrupt your circadian rhythm and affect not only the quality and quantity of sleep:

• Darkness during the day
• Too much light at night
• Eating at the wrong time of day (snacks every time)
• The time on our clocks changes twice a year when we “retreat” and “spring forward“
• Travel across time zones

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