When you eat lots and lots of junk foods you are risking your health. You are feeding yourself things that your body doesn't need.
Things you don't need are:
Soda, chocolate, pie/muffin/cake, donuts, oil, ice cream, and salt. Those are all things that you shouldn't take too much of.
If you think drugs are bad, think about this. Drugs hurt our body and so do junk foods. Drugs increase and decrease your body weight and so does junk food. The thing they really have in common is the addiction they give you. When you start doing drugs you think you can stop but you really can't. Then when you start eating junk food it's hard to stop that because now they make junk food so good tasting that you start to want more, more often.
You may not know this but your body needs some fat in it. Otherwise you are going to be severely hurt because you will be so skinny. Your body won't know what to do. What you don't need is to have too much fat on you.
Your body needs protein, minerals, and vitamins. If you are running low on those you can go to your local drugstore and get some vitamins.
You eat when you let yourself get bored, lonely, angry, hungry, or tired. The worst reason that makes you eat is when you get stressed or upset with the current events.
So remember when you eat, think about the effects that can happen if you eat too much or not enough. I'm not saying don't eat. I'm saying think about what you do eat and how much.