Many people report having a bad night's sleep around the full moon, but until now it has largely been attributed as an urban myth.
However, researchers at the University of Basel have the first scientific evidence to show that sleep deprivation and the lunar cycle are, in fact, linked.
Published in the journal Current Biology, the study adds to existing evidence that despite our modern technology, our bodies are still driven by the geophysical rhythms of the moon and we respond to a circalunar clock.
Researchers studied 33 people in two age groups. They slept in labs and scientists monitored their brain patterns along with eye movements and hormone secretions.
Findings showed that during a full moon, brain activity that takes place during deep sleep dropped by 30%. People also took, on average, five minutes longer to fall asleep and had 20 minutes' less shut eye overall.
The participants reported that their sleep was poorer around a full moon and had lower levels of melatonin, which helps to regulate sleep-wake cycles.
Christian Cajochen, one of the study authors, said: "The lunar cycle seems to influence human sleep, even when one does not 'see' the moon and is not aware of the actual moon phase.
"This is the first reliable evidence that a lunar rhythm can modulate sleep structure in humans when measured under the highly controlled conditions of a circadian laboratory study protocol without time cues."
He said this response to lunar cycles may be a relic from the past when the moon played a greater role in synchronising human behaviours, such as reproduction, as it still does with many animals.
The team plans to look further into the impact of the moon on our behaviour, including our cognitive performance and moods.
Previously, studies have shown that more crimes are committed during full moons, with some forces deploying more officers during full moons in summer months.
Last year researchers at Université Laval in Québec also found more mental health patients are admitted during a full or new moon.