For 10 days, the author resided in an underground bunker to investigate sleep, happiness, and health. One crucial lesson she gleaned from this experience.

Lynne Peeples descended 50 feet underground for 10 days in pursuit of comprehending how diet and sunlight impact our emotional well-being.

During the Cold War, a bunker in Arkansas was transformed into an Airbnb, which is now being used by science journalist and author Peeples for his research on "The Inner Clock: Living in Sync With Our Circadian Rhythms."

In an episode of the "Everyday Better with Leah Smart" podcast, she stated that this individual bought an old nuclear missile silo from the government and enhanced it.

She said there was no daylight in the bunker. Peeples obtained permission from the Airbnb host to cover all clocks on digital devices with black tape so she wouldn't know the time while in the bunker.

She stated that red light, which has the longest wavelength, has the least impact on our circadian rhythms.

Peeples aimed to investigate the consequences of disconnecting her internal clocks from the cues they rely on to keep track of time for her book.

Peeples recorded her experience during her stay using voice recordings with the intention of examining the timestamps to assess how closely she adhered to her typical routine, including when she ate breakfast and when she went to sleep.

"I was able to accurately track my daily activities using voice recordings and timestamps, which was miraculous for the first few days," she stated. "Our internal clocks are quite accurate in keeping track of time."

As she continued with the experience, Peeples started to feel "really out of sorts," similar to major jet lag.

""I was completely flipped when I was 12 hours off from everyone else above ground. I felt the effects of that," she said."

Peeples' moodiness, hot and cold feelings, hunger, clouded thinking, and clumsiness occurred when her internal clock was not in sync with her usual schedule.

"Although it was anticipated, experiencing it deeply was quite profound."

'Getting adequate bright light' is necessary for your circadian rhythm

Your circadian rhythm can cause fatigue, insomnia, headaches, or depression, as research by Cleveland Clinic shows. Peeples' experiment also supports this, demonstrating how factors like sunlight exposure can impact your circadian rhythm.

Peeples stated that maintaining calibration requires sufficient morning bright light.

Exposing your eyes to bright daylight within the first hour or two after waking up is beneficial.

In the morning, go for a 15-minute walk and try to be as close to a window as possible. At night, dim the lights in your home before going to bed to prepare your body for sleep.

To ensure optimal functioning of our body systems, it is crucial to align our lifestyle with the 24-hour cycle. This includes proper food processing and strengthening our immune system to fight off pathogens. By doing so, we can improve our overall health and well-being.

Peeples presented a list of factors that can disrupt your circadian rhythm and have a broader impact on your sleep quality and quantity.

• Darkness during the day
• Too much light at night
• Eating at the wrong times of the day (snacking whenever)
• Twice a year, we adjust our clocks by changing the time.
• Traveling across time zones

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