Dec 05, 2023 21:00:00

``Lack of sunlight during the day is worse than electric lights at night,'' explains a Nobel Prize-winning chronobiologist

Michael Rosbash , an American chronobiologist and winner of the Nobel Prize in Physiology or Medicine, said, ``Lack of sunlight during the day is worse than electric lights at night.''

Chronobiologist and Nobel Laureate in Medicine Michael Rosbash: 'Lack of sunlight during the day is worse than electric lighting at night' | Health | EL PAÍS English
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Rosbash won the Nobel Prize in Physiology or Medicine in 2017 for his work ``discovering the molecular mechanisms that control circadian rhythms (body clocks).'' Circadian rhythm is a physiological phenomenon that fluctuates in approximately 24-hour cycles, and is involved in regulating appetite, sleep desire, sexual desire, etc., as well as the timing of asthma attacks.

Circadian rhythms exist in most living things, including animals, plants, fungi, and algae, and Rosbash said in his Nobel Prize acceptance speech that ``50% of genes are regulated by circadian rhythms.'' I did. However, in a lecture given in November 2023, he stated that ``at least 70% of genes are regulated by circadian rhythms.''

Regarding the difference in this number, Rosbash said, ``This number has been updated based on the results of the latest research conducted over the past six years.The 50% figure was obtained from rodent studies, In 2019, a large-scale study was finally conducted on the primate baboon, and it was revealed that 70% of genes are regulated by circadian rhythms.

Regarding the origin of chronobiology, Rosbash said, ``Chronobiology began almost 50 years ago through my friend

Jeffrey C. Hall, who was a professor at the same university as me. 'I worked in genetics and understood circadian rhythms, and I had research expertise that could be helpful to his work.'

Rosbash conducted research on circadian rhythms using Drosophila melanogaster. However, flies only have 100,000 neurons, whereas humans have 86 billion neurons. Regarding the reason for linking the circadian rhythms of flies and humans, Rosbash says, ``Although mammals have a larger number of neurons, what happens in the neurons is basically the same. 'I started using it as a point of contact for more general questions about neuroscience and behavior.'

Regarding the role of the circadian rhythm, which has a period of 24 hours and 15 minutes, Rosbash said, ``We don't know about humans, but we have information from other animals. , there are animals that are seasonal in terms of reproduction. Their physiology changes with the seasons, and the length of the day also varies with the seasons. To control their reproductive physiology, these animals offset their circadian rhythms. We compare it to the length of the daylight cycle, or the amount of sunlight, which varies throughout the year.This is just a guess, but we suspect that sheep and rodents use circadian rhythms as a tool to measure seasonal changes. Isn't there?' he said.

One thing that flies and humans have in common is sleep and naps. When asked about the biological purpose of sleep and naps, Rosbash said, ``We don't know the details, but we do know that memories are strengthened during sleep, and the morphology of nerve cells changes during sleep.'' However, I don't think this is the main purpose of sleep, and I don't know what fly and human sleep have in common. My guess is that important energy within cells 'I think it may be related to metabolism, such as recharging the source of

adenosine triphosphate (ATP). The brain is the largest consumer of ATP, so it probably needs to be recharged metabolically.' I expressed my own opinion.

In modern times, displays are everywhere, and there are many people who continue to look at their smartphone screens before going to bed. Regarding the negative effects that these habits have on humans, Rosbash said, ``Being exposed to lightning at night is a problem, but it is difficult to estimate the seriousness of it.'' A new study shows that a lack of sunlight during the day is worse than being exposed to electric lights at night. It also appears that many sleep problems can be improved by addressing these environmental factors.

Additionally, in a study of people camping in nature for several weeks, subjects who were exposed to less electric light had better sleep quality and developed a habit of going to bed after dark and waking up in the morning. It is clear that improvements have been made. Another study conducted in Brazil comparing the sleep habits of people living in jungles and people who moved to urban areas found that people who moved to urban areas and were more exposed to electric lights had worse sleep quality. However, it has been confirmed that the timing of falling asleep is delayed. Citing these findings as an example, Rosbash said, ``People today seem to be a little sleep-deprived.If you turn off the lights in a seminar room at 4pm, half the audience immediately starts snoring. 'This kind of thing doesn't happen to people who are well-rested. This is a completely sleep-deprived culture,' he said, pointing out that modern people, who spend their days under bright electric lights, are clearly sleep-deprived. doing.

A study by the International Agency for Research on Cancer (IARC) has revealed that workers who engage in shift work or night shifts are at risk of developing cancer . For people in these jobs, Rosbash says, ``The trick is to act like night is day, or vice versa. You avoid most problems because you don't know what's at night. What matters is how much light gets in and when you eat. Get 8 hours of sleep in a room with no light. 'If you take a break, make sure your sleep is uninterrupted, and don't eat during that time, your body won't notice a difference. The only problem will be your interactions with family and society.'

Also, regarding the reason why snacking at night increases the risk of obesity and metabolic syndrome, ``One hypothesis is that it is related to the DNA damage repair system that is regulated by circadian rhythms. Sometimes they produce toxins to avoid being eaten, such as psoralen. Nighttime snacking introduces toxins that humans are not ready to eliminate at that time, leading to cancers such as colon cancer in the United States. There is also a theory that the prevalence of epithelial cancer may be due to nighttime snacking,' says Rosbash.