Sleep varied to a greater extent across the lunar cycle in men
Sleep disorder collectively refers to conditions that affect sleep quality, timing, or duration and impact a person's ability to properly function while they are awake. In an odd-thing scientifically, the Moon, including its cycles, have long been examined for the investigation of their effect on human sleep, although the outcomes of such analyses have been rather inconsistent.
The researchers concluded that the lunar cycle may affect sleep in humans, with more pronounced sleep alterations in men than women.
The thinking goes that the increasing brightness of the waxing Moon – reaching an optical crescendo on the night of the full Moon – should affect human sleep detrimentally overall, given people generally tend to sleep better with more darkness.
In this research paper, a team of scientists monitored the sleep of over 850 people in Uppsala, Sweden's 4th largest city, using polysomnography measurements (a test used to diagnose sleep disorders) to ascertain their sleep onset, duration, and quality for a single night. These one-night measurements were recorded in individuals over several years (November 2001 to February 2004), across both men and women.
Image Credit ~ NASA |
For each investigated study night date, data was retrieved on the moon's fullness for Uppsala location from www.timeanddate.com (May 2021). Researchers then assigned days of sleep recordings to two lunar phases:
waxing phase, i.e., between the first day after new moon until the day
of full moon (i.e., ~100% of the moon's face is illuminated by the sun);
and waning phase, i.e., the first day after full moon until the day of
new moon (i.e., moon is between earth and sun).
The thinking goes that the increasing brightness of the waxing Moon – reaching an optical crescendo on the night of the full Moon – should affect human sleep detrimentally overall, given people generally tend to sleep better with more darkness.
With this study, Researchers then found -
- Moon's effects much more pronounced in men.
- Women in the study slept on average almost 12 minutes less on nights during the waxing period, compared to waning nights.
- Men slept over 20 minutes less on the waxing nights
- Men have 3.4% lower sleep efficiency, more wakefulness, and larger disruptions to the lengths of sleep stages during waxing nights.
- No correlation between age and lunar phase for any of the sleep parameters.
Christian Benedict, a neuroscientist and first author of the study, from Uppsala University, said -
We used one-night at-home sleep recordings from 492 women and 360 men. We found that men whose sleep was recorded during nights in the waxing period of the lunar cycle exhibited lower sleep efficiency and increased time awake after sleep onset compared to men whose sleep was measured during nights in the waning period. In contrast, the sleep of women remained largely unaffected by the lunar cycle. Our results were robust to adjustment for chronic sleep problems and obstructive sleep apnea severity
Advertisements