Men’s sleep quality may depend on the Moon cycles

UPPSALA, Sweden — Fellas, the next time you find yourself tossing and turning in bed, you may want to blame the Moon. Researchers from Uppsala University in Sweden report that the sleeping patterns of men may be more sensitive to the lunar cycles than those of women. The research team concludes that men may sleep poorly during the first half of the lunar cycle.

We know the Moon influences the tides, but sleeping patterns too? Plenty of earlier studies have attempted to investigate the relationship between the lunar cycle and sleep, but the results have largely been inconclusive and inconsistent. Some have found a connection, others claim no association at all. Most of those prior projects, however, failed to consider and account for factors known to effect human sleep, such as obstructive sleep apnea or insomnia.

“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,” says corresponding study author Christian Benedict, Associate Professor at Uppsala’s Department of Neuroscience, in a media release.

The Moon’s surface is too bright for men?

During the first half of the lunar cycle (or the waxing period), much more of the Moon’s illuminated surface is visible from Earth. Additionally, during the first phase the moment in which the Moon crosses a location’s meridian gradually shifts to the late evening hours. Conversely, during the second half of the lunar cycle, called the waning period, the amount of illuminated Moon surface visible from Earth decreases. Moreover, the Moon’s meridian crossing moment gradually shifts to daytime hours.

Study authors theorize that the waxing period may interfere with male sleeping patterns because the Moon is reflecting more sunlight in the evening, more specifically around when people typically go to bed. On a related note, recent research has found evidence to suggest that men are more sensitive to ambient light than women.

“Our study, of course, cannot disentangle whether the association of sleep with the lunar cycle was causal or just correlative,” Prof. Benedict concludes.

The study is published in the journal Science of the Total Environment.