A healthy life is very important. China has other words "the body is the capital of the revolution."
First of all, you have to do sports every day. The most important thing is that love sports, like running, playing badminton, etc. Second, to ensure that you eat healthy food every day. Teenagers at the development stage, to be strict with food, eat less or don't eat junk food, fast food. Third, a good night's sleep. Scientific research for middle school students sleep nine hours every day, and early to bed and early to rise body good.
Do the above, you will be healthy.