There is no short, simple answer to the question of how much sleep people really need. Our requirement differs depending on our age and individual needs. For instance, preschool-aged children (3 to 5 years) need between 11 and 13 hours of sleep per night. On the other hand, the elderly may sleep for only three or four hours at a time, with their sleep taken both at night and during the day. What is not in question is that most people do not get enough sleep for their needs. Researchers estimate that approximately 10 percent of Americans are chronically sleep deprived.
Sleep deprivation is associated with a higher incidence of accidents, obesity, diabetes, heart disease and psychiatric problems such as depression. Sleep specialists Donna L. Arand and Michael H. Bonnet say, “There is strong evidence that sufficient shortening or disturbance of the sleep process compromises mood, performance and alertness and can result in injury or death. In this light, the most common-sense ‘first, do no harm’ medical advice would be to avoid sleep deprivation.” But what exactly is sleep deprivation?
Everyone has a night or two when their sleep may be disturbed due to illness, being awoken by noise or the room being too warm, for example. The National Sleep Foundation says there are two different factors at work in determining if you will be sleep deprived or not: your basal sleep need (what you require for functioning at your best) and your sleep debt (the accumulation of lost sleep). Let us say, for instance, that you get your required eight hours of basal sleep for three nights in a row. You might imagine that sleep deprivation should not be an issue. However, you may still find yourself feeling sleepy and unable to concentrate. Despite having slept well during the prior three nights, you may still have a sleep debt to “pay off” from the nights before that.
To make things even more complicated, it is also possible to get too much sleep. Researchers have found that sleep regularly lasting nine hours or more is associated with an increased rate of illness, accidents and death. Depression and low socioeconomic status are two factors related to sleeping for long periods of time.
Two surveys taken by the American Cancer Society that included over a million adult participants found that those who slept seven hours a night had a lower risk of mortality in the following 6 years than those who slept either more or less. All else equal, experts suggest that for most healthy adults, getting 7 to 8 hours of sleep per night is ideal.
To judge for yourself the amount of sleep that is right for you, assess how you respond to different amounts of sleep. Some people function better on less sleep and some need more than eight hours to feel at their best. If you believe you are consistently not getting enough sleep, speak with your physician. He or she will be able to give you some advice about how to increase the quantity and quality of sleep you get. It is definitely worth the effort since getting the right amount of sleep can significantly improve your overall quality of life.