Why is it important for an active teenager to eat healthy?

Teen athletes have a more complicated diet than normal teenagers because they have a more active lifestyle. Not only are they growing, but they are expending energy while exercising. This means that they have a higher metaboliosm and need more calories to keep their bodies going, sports-wise and growing-wise. If they don't eat the right food for their body, then they're performance levels will decrease and their muscles could even start to break down without enough protein. Teen athletes could also develop health problems and have weight problems (gaining and losing) without enough calories.

There are many different activities that a teen athlete can participate in, and "teen athletes may need anywhere from 2,000 to 5,000 total calories per day to meet their energy needs." This however, is not the mandatory amount of calories. Depending on the person, activity, lifestyle, etc. the athlete could eat more or less.

kidshealth.org