If you have trouble sleeping at certain times of the month, it could be because of a full moon. Scientists from the University of Washington say there is a link between the lunar cycle and sleeping patterns. They say that on nights when there is a full moon, people could experience more restless sleep. The reason for this could be the Moon's changing brightness. When there is a full moon, the extra brightness in the night sky could interrupt our sleep. The scientists said: "Moonlight is so bright to the human eye that it is entirely reasonable to imagine that, in the absence of other sources of light, this source of nocturnal light could have had a role in [changing] human nocturnal activity and sleep."
The scientists conducted a study of the sleep patterns of over 500 people. Each person wore a special wristband that tracked their sleep. The study included 98 people from an isolated village in rural Argentina. These people did not have access to electricity and other artificial light sources. Their sleep patterns were compared to 464 people living in U.S. city of Seattle, which has lots of artificial light pollution. The scientists discovered that people in the rural village and in the big city got less sleep on the nights leading up to the full moon. The scientists said the artificial light in cities does not seem to affect sleeping patterns and that, "human sleep is synchronised with lunar phases."