About a Good Night's Sleep

What is the clinical importance of a good night’s sleep?

Sleep is one of our major physiological needs. People deprived of sleep may have an impaired quality of life, memory problems, suppressed immune system and other physiological issues.

A good night’s sleep enables a productive, creative and healthy lifestyle. Sleep rests and restores our bodies. Hormones that are released during sleep help in renewing the body’s cells and tissues. Researchers have also found that sleep helps the body in its defenses against diseases. Most importantly a good night’s sleep helps mental rejuvenation.

Lack of sleep is a common problem shared by many adults who complain of daytime sleepiness and loss of energy. Lack of sleep can result in wide mood shifts, listlessness, depression and difficulty in concentration.

Sleep Myths

  1. Everyone needs eight hours of sleep a night - Eight hours is the average amount of sleep needed. Sleep is an individual need. Most sleep experts agree that feeling fully rested the following day is the way to measure the amount of sleep necessary for that specific individual.
  2. Older individuals require less sleep - Many people tend to get less sleep as they age. However, less time in bed for an older person can be due to a variety of factors, including fragmented sleep caused by nighttime trips to the bathroom to urinate, prescription medications that disturb sleep, hormonal changes, your partners sleeping habits and sleep apnea.
  3. Daytime sleepiness is normal - If a person gets enough sleep at night they should not consistently feel drowsy during the day. While going to bed later than usual can certainly leave you feeling very sleepy and “out of it” the next day, feeling drowsy on a regular basis is not normal and should raise significant concern.

What are the different sleep stages?

  • When you first go to sleep, you begin NREM sleep, also known as “quiet sleep,” and then go through four distinct phases, each one progressively deeper than the other. Stages 1-3 are “light sleep” whereas Stage 4 sleep is deep and is thought to be the restorative stage when the body goes about its various repair functions.
  • During REM sleep, the next major sleep phase, your mind is hyperactive but focused. At this time, your blood pressure rises and then sinks low. Your heart rate races and slows, and your breathing pattern is uneven. Blood flow to your brain increases. Dreams are common and often vivid. Except for a quick fluttering back and forth of your eyelids, there is no noticeable physical motion while you are in REM sleep because your body’s motor system has been shut down.

The percentage of each sleep stage varies by age, with decreasing amounts of REM and deep sleep in older people. The majority of sleep at all ages (except infancy) is Stage 2. REM sleep normally occupies about 20-25% of sleep time. Many factors besides age can affect the amount and percentage of each sleep stage, including drugs (particularly anti-depressants and pain medications), alcohol and sleep deprivation.