Sleep 6 to 8 hours per night (Tip 32)

[pioneer]

A study from the University of Luebeck in Germany found that out of 106 people observed, those who obtained a full night’s rest were three times more likely than sleep-deprived subjects to perform well on cognitive tasks measuring memory, creativity, and problem-solving skills. This is due to the brain activity that occurs during certain segments of sleep.

source: ririanproject.com

[MikeLigalig.com]

I agree. And people who sleep less than 6 hours have a tendency to be irritable and impatient.