The definition of sleep for most of us relates to some duration of time when we are not awake. Studies show that “sleep” has very distinctive stages that cycle throughout the resting or sleeping session. Our brains stay active throughout sleep, but varying things happen during each stage. For instance, certain stages of sleep are needed for us to feel well rested and energetic the next day, and other stages are necessary to help us learn or make memories. Bottom line is a number of health maintenance issues occur during sleep. Upon knowing all of this, it is important to understand that not getting enough sleep is not only dangerous, it is flat out bad for our health and makes it very difficult to maintain a healthy body weight and composition.
If we polled 100 people about how much sleep is appropriate, we would get literally 100 different answers. Research indicates that not only does the quantity of our sleep matter, but the quality of our sleep is equally important as well. People whose sleep is interrupted a lot or is cut short might not get enough of certain stages of sleep. In other words, how well rested you are and how well you function the next day depend on your total sleep time and how much of the various stages of sleep you one obtains each night.
In today’s busy world, many of us have figured how to squeeze more out of 24 hours by skimping on sleep. However, this has a significant price to pay with regard to our health. During sleep, our bodies produce valuable hormones. Deep sleep triggers more release of growth hormone, which fuels growth and helps build muscle mass and repair cells and tissues. Another type of hormone that increases during sleep works to fight various infections. Hormones released during sleep also affect how the body uses energy. Studies find that the less people sleep, the more likely they are to be overweight or obese, to develop diabetes, and to prefer eating foods that are high in calories and carbohydrates. Bottom line is lack of quality and quantity can create an environment where it is easier for the body to create fat.
From a mental perspective, sleep can strongly affect our mood. People who chronically lack sleep are also more likely to become depressed. Studies show that not getting enough sleep or getting poor quality sleep on a regular basis increases the risk of having high blood pressure, heart disease, and other medical conditions.
There are a number of common sleep disorders including insomnia, sleep apnea (sleep-disordered breathing), restless leg(s) syndrome, and narcolepsy. Although sleep disorders can significantly affect our health, safety, and well-being, the good news is they can be treated.
Talk to your doctor if you have any of these signs of a sleep disorder: 
Here are several “sleep hygiene” that are commonly suggested by the experts:
Your family doctor or a sleep specialist should be able to help you.
1 Your Guide to Healthy Sleep: U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES
National Institutes of Health National Heart, Lung, and Blood Institute NIH Publication No. 06–5800, April 2006.