What is compulsive eating?

First you have to think about what normal eating is. Basically eating according to your needs. Those needs can be to manage your mood and try to keep you from sinking into a pit of some kind of mental disorder.

It's part of your emotional defense mechanisms.

That is where compulsive eating deviates from the norm, it is an extension of that. The pattern increases deepens and a temporary measure can become ingrained. The key to dealing with it is to deal with the underlying stressors and tensions that are distorting your eating habits.  Much treatment deals with trying to directly repress the desire to eat, which is trying to solve a symptom as if it's the cause.

Eating is necessary for life, therefore using addiction as a model is inapt. Any definition of compulsive eating should come from the way it actually functions, not from something else which is hardly comparable, drugs are not food. This is important for cure and restoration and should be paramount.

Addiction is mainly a physiological dependence on drugs, that has psychological components. The only thing close to a food addiction is alcoholism, because as well as being a drug or a toxin, alcohol is a food.

As neither are necessary for existence, they can theoretically be stopped completely. Whether they should have to be is a source of debate. It would clearly be better if the excess craving for alcohol could be reversed or removed. If that approach had been taken, that could have informed all reversal of unwanted and excess cravings of all kinds.

That's probably why the urge is to get eating disorders on board with that. To continue that evasion. If a drug addict's system can adapt sufficiently and restore the normal balance of innate opiate production. Then their lucky and may be able to remain drug free. Abstaining from drugs cannot guarantee that, anymore than suppressing excess hunger can guarantee to return it to normal.

Compulsive eating occurs when hunger and appetite signals increase substantially out of proportion to your body's current energy and nutrient needs of the body. Hunger rises through signalling from the whole body, to your brain. It has several main causes, overwhelming mental /or emotional trauma-notably bereavement or separation from parent are just some.