Doctors generally recommend sleeping 7–8 hours per night, depending on age.
However, some people manage perfectly well with much less.
A new scientific study identified a rare genetic mutation that allows certain individuals to stay healthy and alert while sleeping only four hours a night.
This research was conducted by a team from the University of California and the Chinese Academy of Sciences.
They discovered a rare mutation called SIK3-N783Y, studied in genetically engineered mice, which is the fifth known mutation linked to short sleep.
The mutation was found in a healthy woman in her seventies who averaged three to six hours of sleep per night.
Researchers explained that individuals with this natural short sleep pattern perform all bodily functions during sleep more efficiently than most people.
This finding is part of a broader project aimed at identifying people with the Natural Short Sleep (NSS) profile.
In people with the SIK3-N783Y mutation, the body completes processes such as toxin removal, cell repair, and brain cleansing in a shorter time, allowing them to function with less sleep than usual.
Sleep deprivation can cause fatigue, reduced concentration, memory problems, and increased risk of heart disease.
Studying mutations like SIK3-N783Y may help develop strategies to improve sleep efficiency and reduce the negative effects of sleep loss.
To test the mutation’s effect, researchers introduced the gene into laboratory mice.
Mice with the mutation slept about 31 minutes less than normal mice, even after sleep deprivation.
After mild induced sleep loss, mice with the mutation slept 54 minutes less than mice without it.
Although the reduction in sleep among mice is smaller than what is seen in humans with natural short sleep, the finding is significant for animal research.
Researchers hope that further study of the SIK3 gene, already linked to regulating deep sleep, may one day allow people to sleep less while still waking up feeling physically and mentally refreshed.