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

In an effort to better understand how factors like when we eat and how much sunlight we get affect our ability to feel rested, happy and balanced, Lynn Peoples went 50 feet underground for 10 days.

Peoples, science journalist and author of “The internal clock: Living in sync with our circadian rhythms,” found one Airbnb in Arkansas this was once a bunker during the cold war.

“This guy had purchased an old nuclear missile silo from the government and stockpiled it,” she said in an episode of “Every day better with Leah Smart” podcast.

There was “no daylight” in the bunker, she said. Peeples also got permission from the Airbnb host to cover all the clocks on digital devices with black tape so they have no idea what time it is down there.

The lights in the bunker were dim and red. “We know that red is the wavelength of light that least affects our circadian rhythmsshe said.

For her book, Peeples wanted to explore what would happen to her internal clocks “if she were to break away from these signs that they have to tell the time.”

During her stay, Peeples documented her experience through voice recordings, with the plan to use the timestamps to see how well she conformed to her typical schedule — such as when she eats breakfast or when she goes to bed.

“For the first few days it was a miracle because I could look later at timestamps of voice recordings that I made and I was pretty accurate in living a 24-hour day,” she said. “Our clocks inside us show pretty good time.”

But about halfway through the experience, Peoples started to feel “really off,” which she likened to a major jet lag.

“At the ‘worst case’ I was completely turned upside down. I lived my day when everyone else above ground slept. So I was almost 12 hours off,” she said. “I felt the effects of it.”

Peeples began experiencing moodiness, “feeling hot and cold” and hunger after her internal clock was out of sync with her usual schedule. He also noticed that her thinking was more clouded and that she was more clumsy than usual.

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

When your circadian rhythm is out of sync, you can experience fatigue, insomnia, headaches or even depression, according to Cleveland Clinic. The results of Peeples’ experiment further prove what research shows about how certain factors like exposure to sunlight can affect your circadian rhythm.

“To keep that calibration, it’s about getting enough bright light, especially in the morningPeoples said.

“Within the first hour or two of 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 a window as possible throughout the day,” she suggested. at night dim the lights in your home as you approach bedtime to prepare your body for bed.

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 certain pathogens. It’s the best way to “keep all those body systems working better by doing the right things at the right times.” she said.

Peeples also provided a list of things that can disrupt your circadian rhythm and affect more than just the quality and quantity of your sleep:

• Darkness during the day
• Too much light at night
• Eating at the wrong times of the day (snacking always)
• Changing the time on our clocks twice a year when we “go back” and “spring forward“
• Travel across time zones

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