We’ve grown accustomed to the idea that a healthy night’s sleep means one solid block of 7 to 9 hours. But science shows what historical research has long suggested: humans may not naturally be “one-stretch sleepers.”

A sleep routine helps signal to your brain and body that it’s time to wind down. By repeating the same calming habits each day, you reduce stress, fall asleep more easily, and improve the quality of your sleep.

A scientific consensus study by the National Sleep Foundation from 2015, based on over 300 previous studies, concluded that there is no optimal number of sleep hours. Age, genetics, health, lifestyle, and many other factors together determine how much sleep you need