Recently, researchers have found evidence that biological differences between the sexes can affect the circadian rhythm of both humans and mice.
There are many indications that women and men have internal clocks that are set a little differently.
Women are more likely to be morning people and seem to tolerate nocturnal disturbances better than men, according to some research. But why?
There are few studies on the differences between women’s and men’s ‘orchestras’, but animal studies suggest that sex hormones may affect the ‘conductor’, namely the brain.
A study shows that the female sex hormone oestrogen is sensitive to light. When the researchers removed oestrogen in mice, they were less reactive to light.
This means that mice with oestrogen were more likely to be woken by the light, even when they should have been asleep.
“This can be a good thing if you have to travel through several time zones or if you have to perform at night,” Marti says. “But not when you have to go to bed and sleep the morning after your night shift.”
The two American researchers who wrote the Science review wondered if women cope with shift work better than men because they are programmed by nature to take care of children, who can wake quite a lot at night.
But this is currently only a hypothesis.