for reference

http://screamingfatgirl.blogspot.ca/2013/02/this-is-why-youre-fat.html

One of the many aspects of the brain that I've been studying has been something called the HPA Axis. For those who care, this is the hypothalamic-pituitary-adrenal axis. You don't have to understand it, but just believe me when I say that it is an important part of your brain when it comes to stress management and anxiety. When you are a child, if you experience the wrong kind of stress, and I don't mean abuse or serious trauma, your HPA Axis can become compromised in such a way as to create a high likelihood of a variety of disorders.

The HPA Axis is responsible for handling stress hormones and there is a "loop" of activity which handles a negative stimulation, activation of bodily systems to handle the stress of it, and then puts an end to that activation. I'm massively oversimplifying here, but anyone who wants to learn more knows how to do a Google search or ten and can get more details.

The bottom line is that early childhood issues such as insecure attachment to parents, chronic unresolved stress, neglect (even moderate), etc. can create issues in this area of the brain. There are multiple potential consequences including the potential to suffer anxiety disorders and depression. This is, in simplistic terms, due to over-activity in the HPA axis. Another, and this is a theory, but it's a plausible one, is that you can become a compulsive eater.

The way this works is that imbalances in the HPA axis which result in over-activity (from stress) can be slowed down by eating comfort food. Food that is high in carbohydrates in particular can produce more endogenous opiods (e.g., endorphins) and stimulate reward pathways. You can, quite literally, become addicted to food.

Here is the thing, once the HPA Axis is screwed up due to childhood experience, it cannot be made normal again. There is nothing you can do to repair the balance to what it should have been had you not had the stressors that created the imbalance. You can try to replace your food addiction and find something else to stimulate the same pathways such that you slow down the over-activity, but you will never be normal like other people.

FT... one more description. But what about hyperinsulinemia?