The mysteries of our sleep: Circadian Rhythms

“Why do we sleep?” Strangely, This was a question posed to me by my Physics teacher when I was in class 12. Of course, I did not know the answer back then and being a Science student without Biology, I did not care much finding an answer to this (not to mention that it wasn’t a google baba’s era some ten years ago). However, life is famous to have its strange ways and very recently, I met another Ph.D. student in a conference who told me something about his research in the area of ‘circadian rhythms’ or in other words, the biological clock of our body. So this fellow researcher told me about how the circadian rhythm of our bodies when perturbed just like when we face a jet lag, tend to attain their stable equilibrium after some time. Imagine- how this phenomenon so natural to our biological systems can be fitted using mathematical equations of dynamical systems!! More to my surprise, today I learned that the 2017 Nobel Prize in Physiology was shared by the trio-Jeffrey C. Hall, Michael Rosbash and Michael W. Young for their discoveries on how biological clocks and internal rhythms govern human life. Well, this was a reason enough to write this post as my last post of this year. So, the story goes as follows:

We all have this biological clock in our body that is almost perfectly synced with the temperature /light changes during the day-particularly the 24-hour cycle of day and night. It is due to this in-built clock that we feel energized in the morning, and feel sleepy at night and that too specifically at the time at which we sleep or wake up daily. Also, it helps regulate the metabolism of our body. For those of us who have experienced jet-lag can easily relate to this as we can determine something wrong with our systems on not being able to fall asleep at night in a country with a different time zone than where we are habitual of living. To be able to control and understand the root cause of this, scientists have studied the circadian rhythms of fruit flies that have exceedingly similar sleep patterns as mammals but their brains having nearly 1 million fewer neurons than a human brain, making them feasible subjects for experiments. It is also found that more than 70 % of the gene expression in humans is under circadian control.


The 2017 Nobel laureates in Physiology have identified a gene that controls our daily biological rhythm. They found out that this gene encodes a particular protein during the night that gets accumulated in cells, while during the day it gets degenerated. They also identified the critical components of the machinery that runs our biological clock and controls our behavior, hormone levels, sleep, body temperature and metabolism in a 24-hour cycle.

Now if you wonder that how is this research useful?

-Using this knowledge of how and what controls these biological rhythms in our body, researchers hope to improve human health by curing metabolic diseases such as diabetes, sleep disorders, drug efficiencies, seasonal depressions, and even Jet lag.

Sleep is a very mystic thing. Even today, we do not exactly know how do we fall asleep and why is sleeping so necessary to replenish our bodies, help memorize things and much more. I wonder what knowledge will the complete understanding of the circadian rhythms will reveal and what changes can it bring to our lifestyles ?? Can we be able to control our sleep during exams- that is my biggest concern !! With this note let ’s put to sleep the previous year and welcome our New Year-2019, hoping for big scientific revelations that help us understand the universe and make our lives better and easier !!

For more information you may refer to:

  2. Nobel Prize In Medicine Is Awarded To 3 Americans For Work On Circadian Rhythm