Bulimia nervosa is when someone eats a lot of food in a short amount of time and then feels really bad about it. They might try to get rid of the food by throwing up, taking medicine, or exercising too much. This is not healthy for their body and can make them very sick. Just like how we need to take care of our bodies by eating healthy food and exercising, people who have bulimia nervosa need help from doctors and therapists to take care of their bodies too.