Humans, like all animals, need sleep, along with food, water and oxygen, to survive. For humans sleep is a vital indicator of overall health and well-being. We spend up to one-third of our lives asleep, and the overall state of our “ sleep health ” remains an essential question throughout our lifespan.
An average adult needs between 7.5 and 8 hours of sleep per night. “But many people can function with 6 hours’ sleep, and there also some who need 9 hours or more,” says Sudhansu Chokroverty, MD, professor and co-chair of neurology and program director for clinical neurophysiology and sleep medicine at the New Jersey Neuroscience Institute at JFK Medical Center in Edison, N.J.
“The amount of sleep needed to function the next day varies from individual to individual, and is determined genetically and hereditarily,” says Chokroverty, who is also a neuroscience professor at Seton Hall University’s School of Health and Medical Sciences.
Myth 1: Getting just one hour less sleep per night won’t affect your daytime functioning.You may not be noticeably sleepy during the day, but losing even one hour of sleep can affect your ability to think properly and respond quickly. It also compromises your cardiovascular health, energy balance, and ability to fight infections.
Myth 2: Your body adjusts quickly to different sleep schedules. Most people can reset their biological clock, but only by appropriately timed cues—and even then, by one or two hours per day at best. Consequently, it can take more than a week to adjust after traveling across several time zones or switching to the night shift.
Myth 3: Extra sleep at night can cure you of problems with excessive daytime fatigue. The quantity of sleep you get is important, sure, but it’s the quality of your sleep that you really have to pay attention to. Some people sleep eight or nine hours a night but don’t feel well rested when they wake up because the quality of their sleep is poor.
Myth 4: You can make up for lost sleep during the week by sleeping more on the weekends. Although this sleeping pattern will help relieve part of a sleep debt, it will not completely make up for the lack of sleep. Furthermore, sleeping later on the weekends can affect your sleep-wake cycle so that it is much harder to go to sleep at the right time on Sunday nights and get up early on Monday mornings.
Adapted from: Your Guide to Healthy Sleep (PDF) The National Institutes of Health