The most hyped – yet arguably most controversial – week of the science calendar week is here again. The first of this week’s Nobel Prizes to be awarded today is for Physiology or Medicine.

Jeffrey C. Hall, Michael Rosbash and Michael W. Young took 2017’s award “for their discoveries of molecular mechanisms controlling the circadian rhythm”, the internal body clock that dictates when we feel the need to eat and sleep.

The three Americans shared the prize of 9 million Swedish kronor (roughly $940,000) equally. Michael Young of Rockefeller University gained recognition for his research on fruit flies, where he isolated the gene that disrupted the circadian clock. Jeffrey Hall and Michael Rosbash, both of Brandeis University, later furthered the work by discovering the fluctuating levels of protein over a 24-hour cycle that the gene causes. The gene encodes a protein within the cell during the night which then degrades during the day.

Their discoveries explain how multicellular organisms, including plants, animals and humans, adapt their biological rhythm so that it is synchronised with the Earth's revolutions.

Understanding how our bodies keep time has "vast implications" for health, said the Nobel committee, who awarded the prize. When working well, our inner clocks adapt our physiology to the dramatically different phases of the day, regulating critical functions such as behaviour, hormone levels, sleep, body temperature and metabolism.

Yet sometimes there is a mismatch between our internal clocks and external cues such as sunlight and temperature. Most of us are familiar with this sensation when we travel across time zones and experience jetlag. The phenomenon of “social jetlag” is also increasingly worrying as people spend more time in artificially lit environments and use digital devices outside of natural daylight hours. The misalignment between our internal and external clocks continues to be cited as a risk factor for various diseases.

Since the seminal discoveries by the three laureates, circadian biology has developed into a vast and highly dynamic research field, with implications for our health and wellbeing that are still to be revealed.