There’s a simple reason our bodies run on an internal clock, better known as our circadian rhythm. There are certain functions we just can’t do simultaneously, like waking up and falling asleep, or even digesting a large meal while we sleep. In order to adjust for these realities, the body developed a schedule with regards to what it does during the day and what it does at night.
Most of the focus on circadian rhythm has had to do with how it affects our sleep, but recently a number of researchers have been realizing that its impacts far more of our biological processes than we thought.
According to Satchin Panda, who has recently released a book called The Circadian Code, information from the circadian clocks are “present in every organ and every cell, and these clocks tell our brain when to sleep, tell our gut when to digest our food optimally, tell our heart to pump more blood and slow down at another time.”
Though many people frequently like to describe themselves as night owls, Panda explains that this difference is less due to biological factors and more likely due to external factors like bright light sensitivity or late night caffeine that keeps people awake far later than they would without such influences.
Panda explains just how much this biological rhythm affects our bodies. “Our intestines, our stomach, and our gut have circadian rhythms, too. Late at night, just like our brain goes to sleep, our stomach and gut start to shut down. Our intestines and gut don’t move food down the digestive tract, so if you eat late at night, the food just sits there. At the same time, the stomach has a buildup and starts to produce acid.”
He concludes with his hope that humans will be more conscious of controlling lighting to match the light of day, given how much time humans now spend indoors.