The American Health Deficit: Sleep Deprivation                       
By: Dr. Kim Archer, NSCA - CPT, Stephen F. Austin State University, and Dr. Lisa Alastuey, CHES, University of Houston

WAKE UP America, you need to sleep! For many, receiving the required hours of sleep per night is compromised due to the hectic and busy schedules most of us have adopted. Sleep is a required activity each day, NOT an optional activity. Sleep doesn't discriminate against one's race, age, or socioeconomic status. The amount of sleep we get impacts how we think, feel, look, and act, ultimately dictating the quality of our overall health.

Sleep is a behavioral period of rest and recovery from the stresses of wakefulness important for normal motor and cognitive functions. All mammals and birds require sleep. In fact humans spend approximately one-third of our lives asleep. Required sleep hours are based on the size of the mammal. For example a cat sleeps about 14 hours per day, and a horse sleeps two and a half hours per day. As humans, adults require approximately eight hours of sleep per night, whereas children require nine hours of sleep per night (Passer & Smith, 2004).

Even though the precise functions of sleep aren't exactly clear, the specific process is well defined and understood. Circadian rhythms, the 24-hour cycle of physiological and behavioral functioning, facilitate the changes from sleeping to waking to sleeping, and so on. Maintenance of the circadian rhythms is controlled by the suprachiasmatic nuclei (SCN) and external environmental cues. The SCN is also called the internal "biological clock" because it controls body temperature, alertness, and activity. During daytime, these controls become active by stimulating wakefulness, and inactive at night acceding to relaxation of the body. The SCN is also responsible for the release of a hormone called melatonin that will help induce sleep, and human growth hormone that will assist in repairing damaged body tissues (Von Dongen, Maislin, Mullington, & Dinges, 2003). Adenosine, a waste product of cellular activity, will decrease during sleep, which will result in a body that feels refreshed and reconditioned (Dement & Vaughn, 1999). External environmental cues, such as artificial or natural light penetrating the eyes, will cause the SCN to slow secretion of melatonin resulting in an increase in activity (Von Dongen, Maislin, Mullington, & Dinges, 2003). Furthermore, light from a lamp or computer screen could delay the transition to the sleep cycle.

The sleep/wake cycle can function even without the indication of light for humans, however the daily cycle will be several minutes longer than 24 hours. A person's body will adjusts its biological clock every morning to the next 24 – hour phase, and can bear 1 – hour alterations (Dement & Vaughn, 1999). Situations that cause a genuine calamity to an individual's biological clock may include changes in the sleep/wake cycle, working night shifts, or traveling across time zones (Akerstedt, Fredlung, Jansson, & Gillberg, M, 2001).

The composition of sleep consists of two distinct phases called non-rapid eye movement sleep (NREM) and rapid eye movement sleep (REM). A majority of our time is spent in NREM (i.e., 75% of the night with four distinct stages) where brain waves, heart rate, breathing, and muscle movement slow in activity, causing the individual to enter a deep sleep. REM (i.e., 25% of the night) phase is distinguished by noticeable eye movement beginning 70 to 90 minutes after a person has fallen asleep. Dreams occur during the REM phase of sleep. REM sleep provides a considerable amount of cognitive benefits, such as storing information into long-term memory, problem solving, creative ideas, concentration, and the ability to learn new skills. REM and NREM (in stages 3 and 4) both provide physical benefits including improved immune functions, growth, repair of tissues, appetite control, and providing energy to the brain and body.

At the conclusion of the REM stage, a sleeping individual will cycle between NREM and REM stages. Individuals will typically experience four to five sleep cycles per night (Coren, 1996; Dement & Vaughn, 1999; Drummond, Kuchinsky, Solamat, Brown & Gillin, 2002; NSF, 2007). Sleep deprivation can create serious health distress. The primary symptom of sleep deprivation is daytime drowsiness (Dement & Vaughn, 1999). Potential negative consequences of a sleep deficit may include:

• Irritability, frustration, nervousness, and difficulty handling stress.
• Impaired reaction time, coordination, and judgment.
• Reduced school/job performance, lack of socialization, and an inability to learn new skills.
• Increase susceptibility to infections, intensified pain, and an increased risk for injury.
• Weight gain, memory difficulties, and poor skin integrity.

(Akerstedt, Fredlung, Jansson, & Gillberg, 2001; Baylor & Carallero, 2001; Gilyatt, 1999; Garbarion, Nobili, Beelke, & et al. 2001).

Foods that contain Tryptophan, an amino acid, serves as a precursor to serotonin and melatonin both of which induce sleepiness. Suggested foods that may help encourage sleepiness include turkey, potatoes, almonds, bananas, milk and dairy products, and whole wheat bread and oatmeal (Afaghi, O'Connor, & Moi Chow, 2007; AASM, 2007). Foods or products that contain caffeine, or nicotine, can cause a stimulant effect detouring one from entering sleep stages. Alcohol can disturb sleep cycle stages by decreasing REM sleep time. Spicy foods can cause heartburn. Therefore, foods with stimulants, alcohol, and spicy foods should be avoided prior to the desired onset of sleep. It is also suggested that if food is consumed prior to sleep, it should be in smaller portions (AASM, 2007).

A study published in the journal SLEEP finds that cell phone use after bedtime is very prevalent among adolescents, and its use is related to increased levels of tiredness after one year (Online, Poor Sleep Adversely Affected by Adolescent’s Use of Cell Phones After Bedtime, 2008). Parents and caretakers should be aware of the fact that young people today use modern means of interacting and communicating in ways they probably cannot imagine. Communication and staying in touch are important for young people, and they now have the technological advances to stay connected more or less permanently. Some people do this all hours of the night when they should be sleeping.

Junk Sleep, like junk food, is sleep that is neither the length nor quality required to feed the brain with the rest it needs to perform properly at school and at work. Nearly all people have a phone, music system, computer, or television in their bedroom - some possessing all of these. Some individuals fall asleep while watching TV, listening to music, internet surfing, or using other electronic gadgets. From late-night TV, to web surfing the internet, to answering work-related calls and emails, to message texting in the middle of the night, many individuals are operating on junk sleep. Junk sleep is also common among some adults who end up living in one time zone and working in another time zone (Online, “Junk Sleep” Damaging Teenager’s Health, 2008).

One out of every three Americans suffers from a sleeping disorder (Online, Sleep Wake Disorders Center of South Florida, 2008). For instance, sleep apnea is a related breathing disorder that causes your body to stop breathing during sleep. It is quite common with obesity being a major risk factor. Dyssomnia (i.e., insomnia, sleeplessness, wakefulness) includes four basic kinds of insomnia: difficulty falling asleep, difficulty staying asleep, waking up too early, and poor quality sleep. Examples of parasomnia include sleepwalking, night terrors, bedwetting, and narcolepsy.

The following health problems could be worsened by poor sleep:

Good health habits not only include eating a nutritious diet, exercising regularly, and managing stress, but also addressing night time rituals that will help promote a more sound full nights rest. Experts recommend maintaining a constant sleep cycle that involves waking up at the same time every day, which includes weekends and days off. Exercising daily also promotes a good night's sleep, but aim to exercise at least six hours before bedtime. Minimize light, noise, and temperature during periods of sleep. Also, move the clock away, or hide it during sleep, as it could be distracting (Online, National Sleep Foundation).

Of interest, the National Highway Traffic Safety Administration estimates there are 100,000 sleep-related crashes in the United States every year, with 1,550 fatalities and 71,000 injuries. (Online, Drowsy Driving Prevention and Countermeasures, 2008) The National Highway Safety Administration estimates that more than 1500 Americans under age 21 are killed because of car crashes due to drowsy driving every year. In some respects, drowsy driving is very much like drunk driving. A drunk driver is impaired when they are in a crash, and will try to respond, but with a delayed response. On the other hand, a drowsy driver who is falling asleep at the wheel will not realize until impact (Garbarion, Nobili, Beelke, et al., 2001).

The Stanford Sleepiness Scale is a fast and simple tool to help you assess your sleepiness level. Ideally, you want a one rating if it is during the day when you are working. If you are at a three, four, or more on the scale during your day, when you should be feeling like a one, this is a signal that you may have a sleep debt and more sleep should be added to your daily agenda. Take note, most individuals have two peak times of alertness during the day, first at approximately 9:00 a.m. and then again at about 9:00 p.m. Typically, one's alertness will start to decrease around 3:00 p.m., but after that it will start to rebuild again.

Therefore, armed with sleep knowledge, and how to not become another sleep deprived statistic, you can take it to heart when someone says to you, "sweet dreams" as this is more than just an old adage but a nightly ritual for you.

references and resources:

• Sleep Disorders - overview, stages of sleep
• Alcohol's Effect on the Sleep Cycle - How Alcohol Obstructs Sleep. A Short Essay on the Effects of Alcohol
• Sleep Disorders Tips
• Teens losing sleep over technology
  

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