5 Consequences of Lost Sleep

You may sleep as few as 5 hours, or as many as 10, but what's most important is that you get what you need. Here's what happens when you don't.

If you suffer from chronic or even occasional insomnia, have experienced jet lag or pulled an all-nighter and then stumbled into work the next day, you have first-hand knowledge of what happens to your brain-and sometimes your life-when you don't get enough sleep. Things fall apart.

The short of it is: Your brain cells start to misfire when you don't get enough sleep. When your brain cells are dysfunctional, you can't think or speak clearly, your thoughts and speech patterns become dull and slow, your judgment is poor and your reaction time is delayed. You're in a bad mood.

The longer you go without a full night's sleep, the more stress your brain cells experience, and the worse your symptoms become. Hallucinations, immune system breakdown, chronic disease, even death, are all possible. Even when sleep deprivation doesn't result in an all-out tragedy, your capacity to do simple, everyday tasks is greatly compromised.


Asleep at the Wheel

Driving when you're tired can be as dangerous as driving while drunk. Harvard Medical School's Division of Sleep Medicine estimates that approximately 1 million vehicle crashes, 500,000 injuries and 8,000 deaths occur in the U.S. each year as a result of driver drowsiness.

Poor Mental Performance

The longer you are awake, the more pressure there is on your brain to fall asleep. If you're getting too little sleep night after night, that pressure increases to the point where it becomes extremely difficult to stay awake and you literally lose brain power and higher-level cognitive functions, such as logical reasoning. Your thought processing capabilities are impaired and you lose some of your motivation, concentration, working memory and ability to solve problems.

Off Your Game

Any activity that requires coordination is affected by lack of sleep. In addition to poor performance, your risk of having an accident is higher when you suffer from sleep deprivation.

More than a Bad Mood

A lack of sleep and poor sleep quality are directly associated with anxiety and depression. A University of Pennsylvania study found that people who had less than 5 hours sleep every night for a week were not only mentally exhausted, but felt stressed, angry and sad. That's a no-brainer when you think about it. Even after one night of poor quality sleep, most people feel irritable, short-tempered and less able to cope with stress.

Weight Gain

A 2010 University of California Los Angeles (UCLA) review of studies performed between 1965 and 1994 concluded that lack of sleep increases both the risk of becoming obese and staying obese. This study confirms the findings of numerous other studies related to sleep and weight gain, wherein sleep restriction caused hormonal changes in the body that resulted in increased hunger and appetite.




Harvard Medical School Division of Sleep Medicine. "Consequences of Insufficient Sleep."  2008. Web. 27 Aug 2010.



Kohatsu, Neal et al. "Sleep Duration and Body Mass Index in a Rural Population." Archives of Internal Medicine. 2006; 166: 1701-1705. Web. 27 Aug 2010



National Institute of Neurological Disorders and Stroke. "Brain Basics: Understanding Sleep."  21 May 2007. Web. 27 Aug 2010.



Nordin, M. and R Kaplan. "Sleep Discontinuity and Impaired Sleep Continuity Affect Transition To and From Obesity Over Time. Scandinavian Journal of Public Health. Mar 2010: 38 (2) 200-207. Web. 27 Aug 2010.



University of California, San Diego. "Brain Activity is Visibly Altered Following Sleep Deprivation." 29 Jul 2002. Web. 27 Aug 2010