The biological clock of mice can be disrupted significantly if they are placed under stress before they sleep, according to a study by researchers at Waseda University, suggesting that staying up late at night can be bad for humans.
In a recent article published in the British science magazine Scientific Reports, the research team led by assistant professor Yu Tahara experimented with various stress tests on mice, including placing them in a tight space and at high places before they sleep.
They planted special chemical markers in the genes of the mice that illuminate when they are feeling stress.
As a result, the biological clock of some mice was significantly disrupted, with day and night actually inverted in some cases.
The same may be said about humans, the researchers said, adding that disruption of the human biological clock could lead to various diseases and increase cancer risks as well.
Tahara was quoted by NHK as saying children with a lot of homework should finish it in the morning rather than stay up late. In the workplace, employees should stop doing overtime and go home early so they can get enough sleep, he added.