How Sleep Deprivation Affects Your Health
Not all of us realize how closely our sleep and health are related. Some are quick to sacrifice hours of slumber to work longer or to finish a great book.
Recent studies quantify the actual toll that sleep deprivation takes on our bodies, and also address new sources of sleep distraction, including electronic devices.
What is Sleep?
Scientists characterize sleep as an altered state of consciousness, as part of our circadian rhythms, which are 24-hour cycles of changes in physiological processes.
Sleep is governed by our bodies' secretion of melatonin, which increases in darkness.
Typical sleep occurs in approximate 90-minute cycles (described below):
- Stage 1 (Beta): 5-10 minutes
- Stage 2 (Alpha): 10-20 minutes
- Stage 3 (Theta): 15-20 minutes
- Stage 4(Delta): 15-20 minutes
- REM: 10-20 minutes
Stage 1: This is the time when your eyes are closed, but you're beginning to relax into sleep. Your breathing and brain waves slow.
Stage 2: The body is now preparing to enter deep sleep: your heart rate slows and your body temperature drops slightly.
Stages 3&4: These are slow-wave, deep sleep stages where our body restores itself physically and mentally. In general, the first four hours of our sleep are devoted to physical restoration, and the second 4 are devoted to mental restoration.
REM: This type of sleep usually occurs after Stages 3 and 4, and includes paralysis and intense dreaming (although dreaming can occur in all stages). The first REM period usually lasts about 10 minutes with subsequent REM periods lasting longer and longer, up to 1 hour. REM sleep is a very active form of mental activity, similar to being awake.
What is Healthy Amount of Sleep?
According to the AASM (2012) one in five adults fail to get the recommended 7-9 hours of sleep.
- 70 million Americans experience an actual sleep disorder such as insomnia, narcolepsy, sleepwalking, or sleep apnea
- Many other Americans have various stressors that, when left unaddressed, result in poor sleep habits, including adolescents who need 8.5 to 9.5 hours of sleep per night, but are currently averaging only 7.
- According to the National Sleep Foundation, babies to children need 18-10 hours of sleep to develop properly. (Check with your pediatrician.)
The Effects of Inadequate or Unhealthy Sleep
- Chronic sleep loss has been found (Taheri, 2004) to increase body weight. Poor sleep triggers an increase in ghrelin, a hormone that triggers hunger, and it decreases leptin, the hormone that controls appetite-suppression. Sleep loss also accounts for elevated levels of cortisol, the hormone that promotes calorie storage as fat.
- Lack of proper sleep has also been found to suppress immune function. Sleep deprivation elevates levels of cytokines, which are associated with cancer, diabetes, cardiovascular disease, and other chronic illnesses. Adequate sleep plays a role in our living a longer life.
- Sleep loss can actually cause our body to mimic aging by adversely affecting our metabolic, neural, and endocrine functioning.
- Since the brain needs sleep to repair damage, replenish energy, and grow new neurons, immediate effects of inadequate sleep include impaired concentration, memory, and creativity, as well as increased reaction time, errors, and accidents (Stickgold, 2009).
How to Get the Best Sleep Possible
Since we've seen that sleep is so vital to our health, what can we do to promote healthy sleep habits (often referred to as sleep hygiene)?
- Avoid all forms of caffeine, nicotine, or any other stimulants past noon.
- Avoid alcohol and sleep medications. These result in an initial deep sleep, but then lead to poor sleep during the remainder of your sleep cycles, preventing that Level 3 and 4 restorative sleep of body and mind.
- Exercise regularly to clear your mind, but avoid working out at least 3 hours before bedtime.
- Establish a consistent, relaxing bedtime schedule. This cues your mind that the time to sleep is approaching.
- Create a sleep environment that is dark, quiet, cool, and comfortable.
- Remove stress by practicing deep relaxation techniques, such as the systematic tensing and releasing each individual muscle in your body while breathing deeply and concentrating on the stress leaving your body as you exhale.
- Get the stress out of your mind and down on paper. Keep a journal by your bed, and if a stressful thought occurs, take it out of your mind and commit it to paper. You can readdress that stressor in the morning, if needed.
- And finally, the issue of our time: electronics. The light emitted from computer monitors, iPad screens, TVs, and smart phones closely mimics that emitted by the sun, causing our bodies to lower production of sleep-inducing melatonin. Studies show that the larger the screen and the closer the exposure, the more melatonin is shut down. So, consider a technical shutdown some hours before bed - rediscover the book!
If, after following the above advice for a while, you still are experiencing problems with sleep, consider keeping the National Sleep Foundation's sleep diary and sharing the results with your doctor to help pinpoint your particular cause of poor sleep.