By Jerrold Kram, MD, FCCP
Medical Director, California Center For Sleep Disorders
Centuries ago there was a belief that going to sleep was like dying and waking up was coming back to life. It was not until the 1800’s that scientists began to realize that in fact there was brain activity during sleep and not until the 1950’s the fact that there were different stages of sleep during the night was discovered.
We now understand that in fact humans experience 3 different states of existence, wakefulness, Non-REM sleep and REM sleep. Non-REM sleep has 3 different stages and occurs for about 75% of the night, the remainder REM or Rapid Eye Movement sleep is the state where most dreaming takes place. Yet despite our ability to measure these stages of sleep we actually do not know why we need to sleep and the exact purpose of each stage of sleep. We all know we can’t function without sleep but what exactly takes place during that 1/3 or our lives remains unknown.
We also know that on average adults need about 8 hours of sleep, children more. In our society it is common for us to function on much less sleep than this and in general adults often think they are doing fine on just 6 hours. The truth is that when adults getting just 6 hours are tested it turns out they are not doing nearly as well as they think. It is easy to demonstrate that their thinking, memory and reflexes are much below normal, yet most fail to recognize this in themselves.
You can learn to get less sleep but you cannot learn to need less sleep. We also know insufficient sleep has been linked to a host of medical problems, including obesity. With the obesity epidemic in this country, sleep is an under-appreciated contributing factor. In addition poor and fragmented sleep has been linked to metabolic diseases such as diabetes, decreased immune function, depression, heart disease and even cancer.
So, developing good sleep habits is essential to good health. There are a few common sense habits that we need to embrace. Called “Sleep Hygiene” they include being sure our environment is sleep friendly, meaning a dark, quiet, somewhat cool bedroom. Exercise anytime during the day also improves sleep. It is best to avoid caffeine, alcohol or nicotine close to bedtime, and if you are having difficulty sleeping, completely avoiding any caffeine is a good idea. Having a relatively regular bedtime and wake-time is also beneficial.
If you are well rested you should be able to awaken feeling refreshed without the aid of an alarm clock. If that is not the case and you feel as if you need more sleep, get sleepy anytime you are sedentary, can fall asleep almost instantly then either you are not giving yourself an adequate opportunity to sleep or you might just have a disorder of sleep. If any of these scenarios sound like you, talk to your doctor.