In fact, sleeplessness has been found to be a significant predictor of absenteeism. Insufficient sleep can also be extremely dangerous, leading to serious or even fatal accidents. The National Highway Traffic Safety Administration has estimated more than 100,000 auto crashes annually may be fatigue related. These drowsy driving crashes cause an estimated 1,500 deaths and tens of thousands of injuries and lasting disabilities. This problem has been found to affect drivers aged 25 or under more than any other age group.
Sleep needs vary.
In general, most healthy adults need an average of eight hours of sleep a night. However, some individuals are able to function without sleepiness or drowsiness after as little as six hours of sleep. Others can't perform at their peak unless they've slept ten hours. Other signs are a tendency to be unreasonably irritable with co-workers, family or friends, and difficulty concentrating or remembering facts. REM sleep is when you dream, and is characterized by a high level of mental and physical activity.