Research has shown that teenagers don’t get enough sleep at night and go to school tired. Some experts believe the cause is biological. Others believe that teenagers stay up late because of adolescent distractions. Research showed that teens need eight to nine hours of sleep at night, as compared with eight hours needed for adults. Sleepy school children make crabby classmates, while students who get plenty of sleep are better behaved, according to a new study published this week in the journal Pediatrics. “Extending sleep opens the door to an effective, feasible way to improve children’s health and performance,” said study author Reut Gruber, director of the Attention Behavior and Sleep Lab at the Douglas Research Center in Quebec, Canada. The study , conducted by Gruber and his colleagues wanted to find out if the behavior of elementary school children was affected by how much sleep they got. The researchers, with the permission of parents, enrolled 34 students ages 7 to 11 in the study. These were healthy kids who didn’t have sleep problems or behavior or academic issues. During one week of school, half the students were put to bed earlier than normal, averaging about 27 minutes more sleep a night. The other half stayed up later than their routine bedtime, losing about 54 minutes of shut-eye each evening. The results showed that teachers , who didn’t know the sleep status of the students, reported significant differences in how the children behaved and coped with everyday challenges. Students who were sleep-deprived not only seemed overly tired, but were more impulsive and irritable than their well-rested classmates. They were quick to cry, lose their tempers or get frustrated. Meanwhile it is reported that poor sleep may increase your risk of type 2 diabetes. Not getting enough sleep can wreak havoc on the body s metabolic regulation, according to new research out of the Netherlands. Researchers found that getting just four hours of sleep may impair the body s use of insulin by up to 25%. Insulin resistance can lead to type 2 diabetes (an inability to use insulin to control glucose from food), which, if left untreated, can lead to other illnesses including heart disease. A study revealed that sleeping too little or too much will pack on belly fat. If you re under 40, logging less than five hours, or more than eight hours of sleep every night, may lead to a greater accumulation of belly fat or “visceral” fat. The findings, by North Carolina researchers, ruled out other fat-causing factors including caloric intake, exercise habits, education and smoking.