This sleep ‘sweet spot’ is optimal for healthy aging, study says

7.9 hours? That's too much. 6.3 hours? That's too little. In between? That's just the right amount of sleep you should get each night. Doctors in the journal Nature call it the "sweet spot" that helps to reduce the risk of disease and extend lifespan. Their research found getting too many Zs had the same effect as a sleep deficit -- more signs of accelerated aging on the molecular level. Consistency appears to be more important than the "Goldilocks" amount of shut-eye. The lead scientist on the study told the Washington Post that "consistent sleep time, around six to eight hours per day," is "going to do good for your overall health."