Many teenagers have an insatiable appetite during puberty because rapid growth necessitates a lot of energy. Teens have higher metabolic needs because their bodies are growing and developing so rapidly at this age. Eating disorders and binge eating are also reasons why teenagers continue to eat certain foods even when they know they are unhealthy. When teenagers are going through a difficult emotional period, the first thing that comes to mind is food. Junk food becomes an obsession because it provides comfort, which is fine at first but can lead to problems if consumed in excess.