Do you get enough sleep? With so much homework it's often difficult to get the rest you need. But you need to try, because sleep keeps you healthy and it stops you getting fat. Recently, a group of US scientists did a study   of kids aged between 8 and 13. The study found that if kids sleep for just one extra   hour each day, the chance of their getting fat is cut by about 30 percent . Why? When people don't get enough sleep, they become tired. When they are tired, they don't exercise enough. Also, kids like snacks: If they are awake   an extra hour or two each day,they have more time to eat snacks or other unhealthy foods. So, how much sleep should you get? Scientists suggest 10 to 11 hours a night for kids aged 5 to 12. For older kids, _ . How many reasons are given why people might get fat without enough sleep?
3. 2. 1 None.