8 Shocking Effects Of Lack Of Sleep

Approximately 60% of American adults get less than the recommended eight hours of sleep and 29% report sleeping an average of six hours or less. Chronic sleep deprivation can have grave consequences. Here are eight alarming ways that lack of sleep can affect your health and well-being.

1. Accidents

Sleep deprivation has played a role in several major catastrophes including the Chernobyl nuclear power plant explosion, the partial nuclear meltdown at Three Mile Island, the Challenger space shuttle explosion, the Exxon Valdez Oil Spill and the crash of American Airlines flight 1420. Fatigue is also responsible for more common vehicular accidents. According to the National Highway Traffic Safety Administration, it contributes to an estimated 100,000 car crashes a year in the U.S. Studies utilizing driving simulators have shown that sleep deprivation can lead to a level of impairment equivalent to being legally drunk.

2. Heart Disease

Sleep deprivation is known to raise blood pressure, increase levels of stress hormones, and lower glucose tolerance. In some people, it can lead to irregular heartbeats. All of these factors are precursors to heart disease. A Harvard University study tracked the health of 70,000 middle-aged women. After ten years, 934 had developed the coronary disease and 271 had died from it. Analysis of the data showed that women who slept less than five hours a night were 40% more likely to suffer from heart disease than women who slept an average of eight hours. Another study following 14,000 people over 12 years concluded that lack of sleep increases the risk of heart disease as much as smoking.

3. Weight Gain

The hormone leptin regulates hunger, metabolism and calorie burning. Leptin levels naturally rise during sleep. Sleep deprivation leaves your body with too little leptin, which can result in persistent feelings of hunger even when you’ve had enough to eat. Low leptin levels also slow down metabolism and cause more calories to be stored as fat. In one study, participants slept for nine hours on one night but were only allowed four hours of sleep on another. On the day following sleep restriction, women consumed 329 additional calories and men ate an extra 263. Another study found that people who slept less than six hours a night were 30% more likely to become obese than people who slept seven or more hours.

4. Low Sex Drive

A person who is sleep-deprived is unlikely to be in the mood for love-making. They are more apt to feel irritable, tense, fatigued and drowsy. Lack of sleep also has a direct impact on the production of the sex hormone testosterone in men. In a study published in the Journal of the American Medical Association, young men with an average age of 24 spent eleven nights in a sleep laboratory. They got up to eight hours of sleep on the first three nights but slept less than five hours on the following eight nights. Researchers took blood samples during the last day of the eight-hour and five-hour sleep phases. Five hours of rest reduced levels of testosterone by 10 to 15%, making them similar to levels found in men 15 years older.

5. Depression

Insomnia was once assumed to be a symptom of depression, but recent research has shown it can also be a cause. People with persistent insomnia are five times more likely to go on to develop depression than people who get adequate sleep. Lack of sleep leads to heightened anxiety and a loss of pleasure in life, two factors which increase the potential for becoming clinically depressed. Insomnia also appears to perpetuate depression. Researchers have found that using talk therapy to resolve depressed patients’ sleeping problems can double their chances of a complete recovery.

6. Learning Impairment

Adequate sleep is crucial for learning. Sleep deprived people are less able to acquire new information due to a lack of focus and attention. In one study, fourth and sixth-grade school children went to bed wearing devices that recorded the duration of sleep. For two nights, the children followed their normal sleep routine. For the following three nights, parents were randomly asked either to extend or reduce their child’s sleep time by one hour. The students were given a series of tests at the beginning and end of the study. Those who got the extra hour of sleep performed significantly better and those whose sleep was reduced by an hour performed worse.

7. Alzheimer’s Disease

Research has linked inadequate sleep to the development of Alzheimer’s. In a healthy brain, beta-amyloid protein fragments are broken down and eliminated. In Alzheimer’s disease, the fragments accumulate to form hard, insoluble plaques.

In one study, researchers analyzed the sleep patterns of 70 adults with a mean age of 76. All participants were free from any form of dementia. The scientists used brain imaging techniques to measure beta-amyloid deposition in the brain and compared the results to sleeping habits. They found that shorter overall sleep duration and poor sleep quality were associated with increased beta-amyloid build-up.

8. Premature Death

Research has shown that those who get insufficient sleep tend to die earlier. One large study analyzed data from several countries covering 1.3 million people and more than 100,000 deaths. It found that those who slept for less than six hours a night were 12% more likely to experience a premature death over a period of 25 years than those who regularly got six to eight hours of sleep. A separate study followed 10,000 British civil servants over 20 years. It found that those who slept five hours or less a night doubled their risk of death from all causes.