Sleep: The Key to Health and Happiness

 
Medically reviewed by
Dacelin St Martin, MD
Triple board-certified in Sleep Medicine,
Internal Medicine, and Pediatrics.

 
 
Epidemiology  |  Contributing Factors  |  Symptoms  |  Acute Effects  |  Chronic Effects  |  Treatment

Overview

Chronic sleeplessness is common in today’s world, and its cause isn’t limited to just one factor. Social obligations, family life, work-related stress, chronic conditions, and sleep disorders can all compromise sleep quality.^[1]

A lack of sleep can lead to a host of physical and psychiatric disorders; however, studies show that restorative sleep can help support a healthy and happy life.

Keep reading to find just how vital quality sleep is for overall healthfulness. 

Epidemiology

Our sleep needs vary and change with age, so this can be an issue with population-based studies that are self-reported or use subjective sleep-time measures. 

Those of us who are sleep deficient get six or fewer hours of sleep a night. One-third of adults reported getting 7 hours or less sleep during the workweek. 

In the United States, Hispanic Americans, Black Americans, Native Americans, Alaskan and Hawaiian natives, Pacific Islanders, and adults younger than 65 are more likely to suffer from insufficient sleep on a nightly basis.^[2]

Insufficient sleep is also can be influenced by occupation and industry. Those with rotating shifts, job stress, or extended work hours are more prone to having short sleep durations. One study showed that short-sleep durations may be increasing over time. 

Between 1975 and 2006, the percentage of insufficient sleep increased from 7.6 percent to 9.3 percent. Those who showed an increase in lack of sleep were college-educated males, full-time workers, and African Americans.^[3]

Another study was done that tested over 690,000 children. This study found that sleep had decreased by .75 minutes per year over the last century. This sleep change was more significant in males, and older children and occurred more during the school week.^[4]

Contributing Factors

Insufficient sleep has different causes that vary from person to person. Some factors that may cause inadequate sleep are:

• Social and family responsibilities
• Work demands
• Chronic conditions
• Psychological disorders, like depression, anxiety, and PTSD
• Medications, like stimulants, antidepressants, glucocorticoids, and opioids 
• Neurological disorders, like Parkinson’s or Alzheimer’s disease
• Comorbid sleep disorders, like obstructive sleep apnea, circadian rhythm sleep-wake disorder, restless legs syndrome, and periodic limb movements disorder^[5]
  
  

Symptoms

• Daytime drowsiness
• Problems regulating mood, depression, and irritability
• Problems forming memories 
• Difficulty concentrating
• Poorer quality of life
  
  

Acute Effects of Poor Sleep

1) Physiological Effects

Sleep is still somewhat of a mystery; however, there are theories as to why sleeping is essential for optimal health. What is known for sure is that restorative sleep can positively affect your physiological and mental health, and lack of sleep can have the opposite effect. 

During sleep, growth hormones are at their highest and are critical factors in cell regeneration and the growth of muscles. 

The brain flushes out neurotoxic waste, allowing it to have a clean slate to work from the next day.^[6] Research suggests that sleep also plays a role in brain plasticity, which in turn may have an impact on learning capabilities and consolidating memories.^[7]

2) Psychological Effects

Inadequate sleep can be linked to mental health disorders. Insufficient sleep, napping, or too much sleep at night can be associated with a poor mood that resembles depression or anxiety.^[8]

3) Sleep and Sickness

Sleeplessness may interfere with the production of proteins called cytokines. These proteins help combat sickness and help to promote sleep. If your sleep is disturbed, these proteins cannot ward off invading infections, like viruses and bacteria. 

One clinical trial inoculated subjects with the human rhinovirus to observe how sleep affects the virus’s development. The results showed that subjects who slept less than 5 hours at baseline were almost three times more likely to develop a cold than subjects who slept more than 7 hours a night.^[9]

Chronic Effects of Poor Sleep

1) Sleep & Weight 

On a subconscious level, your body confuses the sensations of fatigue, sleep, and hunger, causing you to eat more, not because you’re hungry, but because you’re trying to compensate for exhaustion.

Over the past 40 years, lack of sleep in adults has grown from 16% to 37%.^[10] One study showed that those who had inconsistent sleep were more prone to be obese, have an altered response to dietary therapy, and have excessive eating.

Research also shows that there is a possible correlation between insufficient sleep, and obesity, however, more research is necessary.^[11]

2) Obstructive Sleep Apnea

OSA affects 22 million Americans. The risk of developing OSA increases with body mass index. One study showed that a 10 percent increase in weight, made a person 6 times more likely to develop OSA. In another study, moderate to severe OSA was present in 63 percent of obese males, and 22 percent in obese females.^[12]

3) Anxiety and Depression

Cumulative poor sleep can lead to a mood disorder that strongly resembles depression or anxiety.^[13]

4) Quality of Life

Sleep deprivation can sideline even the enjoyable aspects of your life. Chronic sleeplessness can rob you of the physical and cognitive fortitude necessary for even the simplest of tasks, like reading a book or watching a movie, socializing with friends, or taking a class at the gym.

5) Heart Disease

A study of subjects aged 20-80 years showed that those getting less than 6 hours of sleep a night had a higher chance of multiple cardiometabolic problems.^[14]

Treatment 

You should seek medical attention if inadequate sleep persists, as your doctor can check for any sleep disorders or other underlying conditions. 

Some practical sleep hygiene tips are as follows:

• Have a consistent bedtime and wake-up time, even on weekends. Doing this will help you regulate your circadian rhythm and bodily functions.
• Do not use electronics at least 30 minutes before bed, as the blue light suppresses the release of a sleep hormone called melatonin.
• Catnaps that are 30 minutes or less are okay; however, longer naps can interfere with your nighttime sleep.
• Gentle stretching before bed can help you wind down.
• Sleep in a dark cool room with blackout curtains.
• Use white noise machines or a fan.
• Avoid cigarettes, alcohol, and heavy meals in the evening. ^[15][16]

Conclusion

Sleep is an essential part of daily life. Not getting enough sleep is a common issue among Americans. Insufficient sleep can affect mental and physical health, and the risks involved with inadequate sleep can become quite serious. 

There are practical ways to combat inadequate sleep that can be done from home. However, if you have difficulty sleeping or feel fatigued throughout the day despite trying some of the recommended practices, it is always a good idea to see your doctor. He or she will help guide you and refer you to a sleep specialist if your symptoms do not improve. 

References:

1. Cirellii, C., Benca, R., Eichler, A. (2020). Insufficient sleep: Definition, epidemiology, and adverse outcomes. In: UpToDate, Post TW (Ed), UpToDate, Waltham, MA. (Accessed January 25, 2021.)
2. Liu, Y., Wheaton, A. G., Chapman, D. P., Cunningham, T. J., Lu, H., & Croft, J. B. (2016). Prevalence of Healthy Sleep Duration among Adults–United States, 2014.  Morbidity and mortality weekly report, 65(6), 137–141. https://doi.org/10.15585/mmwr.mm6506a1
3. Knutson, K. L., Van Cauter, E., Rathouz, P. J., DeLeire, T., & Lauderdale, D. S. (2010). Trends in the prevalence of short sleepers in the USA: 1975-2006. Sleep, 33(1), 37–45. https://doi.org/10.1093/sleep/33.1.37 Ibid, 1
4. Matricciani, L., Olds, T., & Petkov, J. (2012). In search of lost sleep: secular trends in the sleep time of school-aged children and adolescents. Sleep medicine reviews, 16(3), 203–211. https://doi.org/10.1016/j.smrv.2011.03.005Chervin, R., Scammell, T., Eichler, A. (2019). Approach to the patient with excessive daytime sleepiness. In: UpToDate, Post TW (Ed), UpToDate, Waltham, MA. (Accessed January 25, 2021.)  
5. Bonnet, M., Arand, D., Benca, R., Eichler, A. (2021). Risk Factors, Comorbidities, and Consequences of Insomnia in Adults.  In: UpToDate, Post TW (Ed), UpToDate, Waltham, MA.
6. Underwood E. (2013). Neuroscience. Sleep: the brain’s housekeeper?. Science (New York, N.Y.), 342(6156), 301. https://doi.org/10.1126/science.342.6156.301
7. Eugene, A. R., & Masiak, J. (2015). The Neuroprotective Aspects of Sleep. MEDtube science, 3(1), 35–40.
8. Pires, G. N., Bezerra, A. G., Tufik, S., & Andersen, M. L. (2016). Effects of acute sleep deprivation on state anxiety levels: a systematic review and meta-analysis. Sleep medicine, 24, 109–118. https://doi.org/10.1016/j.sleep.2016.07.019
9. Prather, A. A., Janicki-Deverts, D., Hall, M. H., & Cohen, S. (2015). Behaviorally Assessed Sleep and Susceptibility to the Common Cold. Sleep, 38(9), 1353–1359. https://doi.org/10.5665/sleep.4968
10. Spiegel, K., Tasali, E., Penev, P., & Van Cauter, E. (2004). Brief communication: Sleep curtailment in healthy young men is associated with decreased leptin levels, elevated ghrelin levels, and increased hunger and appetite. Annals of internal medicine, 141(11), 846–850. https://doi.org/10.7326/0003-4819-141-11-200412070-00008
11. Greer, S. M., Goldstein, A. N., & Walker, M. P. (2013). The impact of sleep deprivation on food desire in the human brain. Nature communications, 4, 2259. https://doi.org/10.1038/ncomms3259
12. Perreault, L., Pi-Sunyer, F., Kunins, L.Obesity in adults: Etiology and risk factors. (2020). In: UpToDate, Post TW (Ed), UpToDate, Waltham, MA. (Accessed January 27, 2021.)
13. Ibid, 8
14. Ibid, 1
15. Ebrahim, I. O., Shapiro, C. M., Williams, A. J., & Fenwick, P. B. (2013). Alcohol and sleep I: effects on normal sleep. Alcoholism, clinical and experimental research, 37(4), 539–549. https://doi.org/10.1111/acer.12006
16. Spadola, C. E., Guo, N., Johnson, D. A., Sofer, T., Bertisch, S. M., Jackson, C. L., Rueschman, M., Mittleman, M. A., Wilson, J. G., & Redline, S. (2019). Evening intake of alcohol, caffeine, and nicotine: night-to-night associations with sleep duration and continuity among African Americans in the Jackson Heart Sleep Study. Sleep, 42(11), zsz136. https://doi.org/10.1093/sleep/zsz136