Health. Why can some people sleep three hours a night without feeling tired?

Short sleepers could help develop a treatment for sleep problems. Researchers from the University of California, San Francisco (UCSF) and the Shanghai Institute of Materia Medica, the Chinese Academy of Sciences, have identified a genetic mutation in people who sleep between three and six hours a night without negative health effects.

This discovery could lead to a treatment for people suffering from sleep disorders. "Our body continues to function when we fall asleep," explains Ying Hui-Fu, a neurologist at UCSF and co-author of the study. The brain detoxifies by eliminating toxins. The body regenerates.

"In these people, all of the functions our bodies perform while we sleep may simply be functioning at a higher level than our own," the scientist continues on the Nature website .

A test on mice

The study analyzed the genomes of about a hundred people who sleep little. A mutation in the SIK3 gene allows these individuals to regulate their heart rate during sleep, allowing them to get restorative sleep despite the short sleep volume.

Researchers modified the DNA of mice with this mutation to observe their sleep. And the results were telling: they needed 31 minutes less sleep than other mice—this animal sleeps an average of 12 hours a day.

Further studies are needed to identify other genetic changes and better understand the mechanism of sleep.