In Dr. William Dement’s new book, he argues that a good night’s sleep saves lives. “There is plenty of compelling evidence supporting the argument that sleep is the most important predictor of how long you will live, perhaps more important than whether you smoke, exercise, or have high blood pressure or cholesterol level,” says Dement. Dement wants to alert the world about the power of sleep. He feels frustrated that so many people sacrifice sleep to meet the demands of endless days, that unnoticed sleep disorders shorten lives with heart attacks and strokes, and that people fall asleep while driving and cause fatal crashes. “I know about so many tragedies that I can’t even think about them anymore because I start to cry,” Dement said. A healthy person needs about seven to eight hours of sleep to feel wide awake and energetic for the entire day. If you brag that you can get by on just a few hours a night or if you feel you need nine to ten hours of slumber every night to feel good, you may need a sleep checkup. “When people think about sleep, they think about only one problem and that’s insomnia--when it’s really a vast terrain,” Dement says. Other disorders include sleep apnea (when a person stops breathing repeatedly during the night). In his book, Dement reports that every night more than 50 million Americans stop breathing and that apnea annually causes an estimated 38,000 fatal heart attacks and strokes in the United States. Apnea also causes extreme fatigue. Here is the good news: with treatment, sleep apnea can often be cured. When you sleep right, you rise feeling fresh and renewed. Your senses soak up simple pleasures, such as the clean smell of the air. It is Dement’s wish that everyone has that feeling, every day.