Some people are genetically conditioned to need only 5 hours of sleep!

Certaines personnes sont génétiquement codées pour n’avoir besoin que de 4 heures de sommeil !

The ideal sleep duration which allows us to spend our days without feeling any fatigue, is from 7 to 8 hours. But there are people who only 5 hours of sleep set them up for the day without showing symptoms of sleep deprivation.

This difference in the length of needed sleep is explicable in terms of genetics, in fact, scientists have discovered the BHLHE41 gene mutation which reduces the optimal length of sleep and allows some people to content themselves with only 4 hours of sleep.