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Why is Sleep So Important to Health?

October 2007

Karen Ensle Ed.D., RD, FADA, CFCS
Family & Community Health Sciences Educator
Rutgers Cooperative Extension of Union County

Want to improve your physical health? Get enough sleep. Sleep is a basic human need and a natural part of life. While it can be done for a while (and often is), functioning with only 3 or 4 hours of sleep each night will probably cause health problems in the future. This is because sleep is not an “option,” it is something our bodies need to do daily. Even though the exact reasons for sleep remain a mystery, we do know that, during sleep, many of the body's major organ and regulatory systems continue to work actively. Some parts of the brain actually increase their activity dramatically, and the body produces more of certain hormones.

Sleepiness due to chronic lack of adequate sleep is a big problem in the United States and affects many children as well as adults. Children and even adolescents need at least 9 hours of sleep each night to do their best. Most adults need approximately 8 hours of sleep each night.

When we get less sleep (even one hour less) than we need each night, we develop a "sleep debt." If the sleep debt becomes too great, it can lead to problem sleepiness – sleepiness that occurs when you should be awake and alert, that interferes with daily routine and activities, and reduces your ability to function. Even if you do not feel sleepy, the sleep debt can have a powerful negative effect on your daytime performance, thinking, and mood, and cause you to fall asleep at inappropriate and even dangerous times.

Inadequate sleep can cause decreases in: performance, concentration, and reaction times. It can also cause increases in: memory lapses, accidents, injuries, behavior problems, and mood problems. An internal biological clock regulates the timing for sleep. It programs each person to feel sleepy during the nighttime hours and to be active during the daylight hours. A person who has not obtained adequate nighttime sleep is at high risk for symptoms of physical and/or mental impairment.

Problem sleepiness has serious consequences related to health and wealth. It puts adolescents and adults at risk for drowsy driving or workplace accidents. It may mean poor planning of meals and overspending. It increases the risk of poor social relationships, as well as, it effects our personal performance.

Sleep, like diet and exercise, is important for our minds and bodies to function normally. In fact, sleep appears to be required for survival. Rats deprived of sleep die within two to three weeks, a time frame similar to death due to starvation. So think about your daily sleep-wake cycle and try to get more sleep each night. Each small step you take will improve your health.