Healthy eating habits along with regular exercise is the only way to become fit. If we have the correct number of calories (卡路里) and exercise regularly, we will lose weight, keep fit and feel great, too.During teenage years, it is important to give our body the energy(能量) it needs. If we don't eat meals, we won't get enough calories, and then we will feel tired. By the way, calorie is just another word for energy. About 50% of our calories should come from rice, bread, vegetables and fruit. We also need to drink a lot of water, 6 to 8 glasses a day. Drinking enough water will make ou