Human sleep actually synchronizes with the lunar cycle

  fall asleep later on the night before the full moon and sleep less

  Image source: "Science" website

  Science and Technology Daily, Beijing, January 28 (intern reporter Zhang Jiaxin) For centuries, humans have blamed our emotions, accidents and even natural disasters on the moon.

But according to the latest research published in the journal Science Advances on the 27th, the moon also affects another thing-our sleep.

  Scientists from the University of Washington, Yale University and the National University of Quelmus in Argentina pointed out in the paper that the human sleep cycle fluctuates within a 29.5-day lunar cycle: in the days before the full moon, people fall asleep late and sleep for a short time.

  Using a wrist monitor, the research team tracked 98 people living in three communities in the Argentine Province of Formosa.

Two of the communities are located in the countryside and one community is located in the city.

Subsequently, they analyzed the sleep monitoring data of 464 college students from the Seattle area.

Researchers observed the changes in sleep start time and sleep time of these subjects in rural and urban environments, and found that their sleep cycle fluctuates.

  The prevalence of this pattern may indicate that the moon has a significant regulatory effect on sleep.

Our natural circadian rhythm is to some extent synchronized with or connected to the various phases of the lunar cycle.

Even in cities with severe light pollution, this effect may exist.

  Studies have confirmed that on the night before the full moon, subjects fell asleep the latest and slept the least.

This is because with the arrival of the full moon, the first quarter moon gets brighter and brighter, usually rising in the late afternoon or evening, and there will be more natural light after dusk.

Although there will be obvious light during the second half of the moon's surplus and moon's waning, the moon rises late.

Studies have also shown that light affects sleep.

People in urban areas sleep later and sleep less than people in rural areas without electricity.

  Whether the moon affects our sleep has always been an issue of debate among scientists.

Some studies have hinted at the influence of the moon, but they contradict other studies.

This new study shows a clear pattern, partly because the research team uses a wrist monitor to collect sleep data, rather than other methods reported by users.

In addition, the researchers tracked different lunar cycles, which helped filter out disturbances in the data, including individual differences in sleep patterns and the presence of lights.

  "We assume that the sleep pattern is an innate adaptation, that is, the cyclical changes of the moon enabled our ancestors to use this natural light source." The lead author of the study and a postdoctoral fellow in the Department of Biology at the University of Washington, Leandro Casiraji said.