By DeLois Weeks, RN, PhD
Sleep studies consistently show that sleep plays a vital role in promoting physical health, longevity, and emotional well-being. After a good night's sleep, we feel better, our thoughts are clearer and emotions are less fragile. Without adequate sleep, judgment, mood, and ability to learn and retain information are weakened. Sleep improves our memory, increases concentration, and enables the brain to more effectively process new experiences, knowledge and understanding.
During sleep, repairs are made to the body, and extra protein molecules that boost the immune system are produced. Sleep helps reduce stress. It also helps to control weight gain by regulating hormones affecting appetite. People who report sleeping less than five hours a night have been found to be more likely to become obese than those who sleep seven to eight hours a night.
Research indicates that sleep reduces the chances of Type 2 Diabetes by affecting metabolism of glucose (carbohydrates cells use for fuel/energy). Adults sleeping less than five hours a night are at greater risk of developing Type 2 Diabetes.
Requirements for sleep vary by individual: The National Institute of Neurological Disorders and Stroke reports that most adults need 7-8 hours a night. Some people may need as few as 5 hours per night and others up to nine or ten hours of sleep each day for proper functioning.
Sleep reduces agitation, moodiness, depression and anxiety. It also decreases high levels of "inflammatory markers" like C-reactive protein and alpha lipoprotein both linked to heart disease and stroke. Sleep helps regulate blood pressure and cholesterol levels (both play a role in heart disease).
Sleep Requirements by Age
Number of Hours
Newborns (0-2 months old)
Infants (3-11 months old)
Toddlers (1-3 years old)
Pre-school children (3-5 years old)
School-aged Children (5-10 years old)
Teens (11-17 years old)