According to the latest research published in Science Advances, our sleep patterns are affected by the repulsions and pulls of the moon tides.
The findings of the study show that on the days leading up to the full moon, people go to bed late and sleep less. A lunar cycle takes 29.5 days to complete.
Changes in sleep time for each participant during the lunar cycle ranged from 20 to more than 90 minutes and did not differ significantly between groups.
Study participants live in environments ranging from a rural environment with and without access to electricity in indigenous Toba / Qom communities in Argentina to a highly urbanized post-industrial environment in the United States.
Sun and moon data up to the registration dates for the Ingeniero Juárez site were obtained from NASA’s Jet Propulsion Laboratory HORIZONS Web Interface.
Moonlight, which is primarily present in the early hours of the night, is more likely to cause changes in the onset of sleep. Conversely, during the late night when most individuals are typically asleep, moonlight should have little effect on sleep onset or duration.
While the sun is the most important light source for almost all species and the synchronizer of circadian rhythms, moonlight also regulates nighttime activity in organisms.
The moonlight is so bright to the human eye that in the absence of other light sources, it is perfectly logical to imagine that this night light source could have a role in modulating human nighttime activity and sleep.
Before the presence of artificial light, moonlight was the only light source sufficient to stimulate nighttime activity; Still, the evidence for modulation of sleep timing according to moon phases is controversial.
The study shows that sleep starts later, and the hours after dusk are shorter on the nights before the full moon when moonlight is present.
Both the duration and the time of sleep onset showed a clear modulation throughout the lunar cycle, clearly visible in the entire population and in individual populations.
The study predicts that in communities without access to electricity, moonlit nights will be associated with increased nighttime activity and decreased sleep.
The amplitude of the moon phase effect over sleep parameters, the more limited the access to electric light, the stronger it seems.