Too Much or Too Little Sleep Raises
 Your Diabetes Risk
Both too little and too much sleep could increase your risk of type 2 diabetes.
A 15-year study of more than 1,000 men found that those getting less than six or more than eight hours of sleep a night had a significantly increased diabetes risk.
The risk was roughly twice as high for those sleeping relatively short periods, and more than three times as high for those who slept for long periods. Those who slept for seven to eight hours a night were at the least risk.
A similar pattern has been observed in the relationship between sleep and coronary heart disease.
Diabetes Care March 2006; 29(3): 657-661
MSNBC March 10, 2006

The Dangers of Oversleeping

  Global sales for sleeping pills will pass $5 billion in the next several years, and the number of young adults using sleeping pills recently doubled over a four-year period. However, above and beyond the many known dangers of the pills themselves, excess sleep itself may be unhealthy.

 A six-year study of more than 1 million adults has shown that patients who got between six and seven hours of sleep a night have a lower mortality rate than those who got eight hours. In fact, the lead researcher on the study believes that there is little evidence supporting the notion that a patient who sleeps eight hours a night functions any better than one who sleeps no more than seven hours.

Moreover, another study has shown that those who sleep half that much -- 3.5 hours -- live longer too.

The actual number of Americans with real sleep problems is unclear, because the statistical information lumps insomnia, jetlag, sleepwalking, bed wetting, night terrors, sleep apnea, narcolepsy and other disorders into one catch-all category.
Live Science March 23, 2006