Sleep deprivation Sleep is essential for human health, just as eating healthy food or getting enough exercise.. Getting enough sleep is crucial for physical and mental health, and insufficient sleep can lead to various health problems. For optimal health, most healthy adults need 7 to 9 hours of sleep per night. Experts suggest that adults should aim for at least 7 hours of sleep each night. Variations: While 7-9 hours is a common guideline, individual sleep needs can vary. Newborns typically sleep 14-17 hours a day in short bursts, waking frequently to feed, while older babies (4-12 months) generally sleep