This is also consistent with prior data that indicated that insufficient sleep during adolescence increased feelings of depression, anxiety, and moodiness (Brody, 2007). In the last few years, researchers have concluded that a significant percentage of car accidents (especially single vehicle accidents) are attributable to sleepiness behind the wheel and that sleep deprivation actually impairs driving ability and reaction time as much as driving under the influence of alcohol (Siegel, 2005). Likewise, chronic sleep deprivation undermines work productivity, because its effects are cumulative.

Our daily schedules normally dictate how much we sleep, and because we are able to function even without enough sleep, many of us do not realize that we are getting too little sleep until we have the opportunity to vacation without the need to follow any particular schedule. According to researchers, clues that we are sleeping less than we need include difficulty concentrating and napping during the day (Brody, 2007).

Sleep Deprivation and Specific Health Risks:

Aside from obvious behavioral consequences of sleep deprivation, there are apparent links between sleep and serious diseases like diabetes, hypertension, depression, obesity, and heart disease, although sleeping too much seems also to correspond to increase of these conditions. The data suggest that people who sleep the most and the least are afflicted by these conditions more than people who sleep approximately 7 or 8 hours per night (Brody,...

The mechanisms by which sleep affects health are not yet understood, but preliminary indications are that sleep deprivation reduces the body's ability to produce certain essential hormones, such as insulin and leptin, corresponding to increased risk of diabetes and obesity, respectively (Brody, 2007). Long-term studies of adult women yielded similar results, indicating that those who slept too little were more likely to become obese and that those who slept too much (i.e. more than 9 hours per night) suffer from increased rates of developing Parkinson's Disease (Brody, 2007).
Finally, the connection between obesity and sleep deprivation is even stronger in light of studies conducted in England linking short-duration sleepers at the age of 2.5 years to obesity at age 7 (Brody, 2007). More research is needed to determine the exact relationship between sleep and human health, but the implications of what we have already learned only underscore the importance of continued investigation.

References

Siegel, J.M. Clues to the Functions of Mammalian Sleep Nature 437, 1264-1271 (October 27, 2005). Retrieved November 17, 2007, from natureonline.com, at http://www.nature.com/nature/journal/v437/n7063/full/nature04285.html

Brody, J.E. Personal Health: At Every Age, Feeling the Effects of Too Little Sleep; the New York Times. (October 23, 2007). Retrieved November 17, 2007 from nytimesonline.com, at http://www.nytimes.com/2007/10/23/health/23brod.html?_r=1&oref=slogin&pagewanted=print