Moon Cycle Has Distinct Effect on Sleep, Study Finds | To sleep

Folklore has loaded the moon with major responsibilities: moods, spikes in crime, and even psychosis are blamed on Earth’s one constant natural satellite. But could the “moon effect” interfere with sleep?

Scientists have long known that human activity is facilitated by light, be it sunlight, moonlight, or artificial light. But one study suggests that our ability to sleep is markedly affected by the lunar cycle, even when accounting for artificial light sources.

Using wrist monitors, researchers tracked the sleep patterns of 98 people living in three indigenous communities in Argentina over a period of one to two months. One rural community had no access to electricity, a second rural community had limited access to electricity, while a third community was located in an urban setting and had full access to electricity.

Participants from all three communities showed the same pattern of sleep oscillations as the moon progressed through its 29.5-day cycle, with sleep duration varying between 20 and over 90 minutes, and bedtime varying from 30 to 80 minutes.

In each community, the peak of participants who slept less and stayed awake later occurred in the three to five day period leading up to full moon nights, and the reverse occurred on the nights leading up to the new moon. , noted the authors.

The data was somewhat surprising, as the initial expectation was for less sleep and more activity on full moon nights, said study author Horacio de la Iglesia, professor of biology at the University of Washington. “But it turns out that the nights before a full moon are the ones that get the most moonlight during the first half of the night.”

Unsurprisingly, the data showed that the “moon phase effect” on sleep appeared to be stronger as access to electricity was limited.

In an attempt to corroborate their findings, the researchers compared their findings to data similarly collected from 464 Seattle-based and University of Washington students. They found the same oscillations in sleep patterns.

“Together, these results strongly suggest that human sleep is synchronized with lunar phases regardless of ethnicity and socio-cultural background and level of urbanization,” the researchers wrote in the journal Science Advances.

De la Iglesia added, “We humans tend to believe that we have been successful in controlling nature in one way or another, and the use of artificial light is a prime example. But it turns out that there are some forces of nature that we cannot walk away from.

Derk-Jan Dijk, professor of sleep and physiology and director of a center for sleep research at the University of Surrey, noted that the researchers had not addressed internal influences such as circadian clocks that could affect sleep patterns.

Previous research on the moon’s effects on sleep has been inconsistent: studies have looked at sleep in the lab (where external light is shielded) and most have not been designed to specifically examine the moon’s impact. said Dr Ciro della Monica, researcher at the Surrey Sleep Research Center.

“The study is very interesting but, as the authors themselves state, they cannot establish causation,” said Della Monica. “However, the data is strong and new.”