What is the lunar effect?
“Emergency rooms get busy on full moon nights.” “More babies are born at the full moon.” “There are more crimes and accidents.” The idea that the phases of the moon affect the human body and mind is called the “lunar effect,” known in Japan as “the moon’s magic power.”
The moon has long been thought to have mysterious power. The English words “lunacy” and “lunatic,” meaning madness, come from the Latin for moon (luna), reflecting the belief that people lost their minds when bathed in the light of the full moon. The legend of the werewolf, a man who turns into a wolf on full moon nights, is also tied to this idea.
The book How the Moon Affects You
The phrase spread in Japan through a 1978 book by the American psychiatrist Arnold L. Lieber (Japanese title Tsuki no Maryoku). Lieber claimed that murders and other crimes increase around the full and new moon, and proposed a theory of “biological tides,” suggesting that the water in the human body might be affected by the moon’s gravity like the tides.
What does science say?
Since then, many researchers have examined statistics on the number of births, emergency room patients, crimes and accidents. Most found no clear link with the full moon. The moon’s gravity raises tides in huge masses of water like the sea, but its effect on something as small as the human body is thought to be tiny.
People remember striking events like “it was busy on the full moon night” and tend to forget full moon nights when nothing happened. This “memory bias” is said to sustain the legend of the lunar effect. On the other hand, some research suggests that sleep may be lighter on bright full moon nights, and debate continues.
Moon legends of the world and Japan
In Japan, the moon has been told of as a beautiful and mysterious world, as in the moon rabbit and the tale of Princess Kaguya. At the same time, many regions have sayings that you should not stare at the moon for long.
