The 2017 Nobel Prize in medicine has been given to three scientists “for their discoveries of molecular mechanisms controlling the circadian rhythm”, or the biological clock. Their work helped illuminate one of the central mysteries of human life: why we need sleep, and how it happens.

Jeffrey C Hall, Michael Rosbash and Michael W Young were given their award for understanding the mysteries of how life tracks time and changes itself according to the movement of the sun.

Circadian rhythms are the ways that the body keeps itself regulated with the passing of the day, and that the process can affect sleep, behaviour, hormone levels, body temperature and metabolism. They show why disturbed sleep – like in the case of jet lag, or people with insomnia – can have terrifying knock-on consequences, like an increased risk of various diseases.

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The researchers discovered that all types of life on Earth – from plants to humans – regulate their body clock using the sun, with special technologies inside the body. They showed how the body clock can disrupt the central ways the body works, including things like metabolism, and explained how if it is thrown off it can cause huge problems for people and other parts of life.

The researchers “were able to peek inside our biological clock and elucidate its inner workings”, according to the Nobel committee’s citation for the more than $1m (£750m) prize. The discoveries “explain how plants, animals and humans adapt their biological rhythm so that it is synchronized with the Earth’s revolutions”, it said.

The work didn’t reveal any tips for regulating our own circadian rhythm or improving sleep, said experts. But it was a reminder of the importance of doing so – and of keeping good sleep hygiene, by ensuring that people maintain good sleep patterns and keep themselves in sync with the sun, they said during the press conference.

The win comes soon after one of the world’s leading sleep scientist argued that a “catastrophic” lack of sleep is slowly killing us and spreading damage throughout society.

The laureates used fruit flies to isolate a gene that controls the normal daily biological rhythm and showed how this gene encoded a protein that accumulates in the cell during the night and degrades during the day.

Thomas Perlmann, secretary at the Karolinska Institute Nobel Committee, described the reaction of Rosbash when first informed of the award: “He was silent and then he said ‘you are kidding me?’.”

Medicine is the first of the Nobel Prizes awarded each year. The prizes for achievements in science, literature and peace were created in accordance with the will of dynamite inventor and businessman Alfred Nobel and have been awarded since 1901.

Nobel medicine laureates have included scientific greats such as Alexander Fleming, the discoverer of penicillin, and Karl Landsteiner, whose identification of separate blood types opened the way to carrying out safe transfusions.

The prize has not been without controversy, especially with the benefit of hindsight, such as with 1948 award for the discovery of DDT, a chemical that helped battle epidemics but was later banned due to its harmful environmental impact.