Is the desire to overeat mental or physical or behavioral?
That is a big question in a way. Previously, I defined six categories of problems that lead to overeating: Lack of food knowledge, physical, environmental, psychological maladaptive behaviors, social, and addiction. http://philosophyofweightmanagement.blogspot.ca/2015/09/edited-thinking-time.html We can re-slice these a number of ways.
Does it have an internal cause or external? Ultimately, we need to deal with the problem in a internal fashion, but we are not responsible for the environment we were raised into, nor are we responsible for the family or cultural bullshit that we need to learn to cope with. We learn from our families; when they are wrong, we learn wrongs. This is the simple "obese" parents raise obese children, yet the parents are not necessarily fat. Obesity generates out of a way of thinking. We can blame our parents, our affluence, our environment, the times, chemicals, and yet it will be thrown back on us as we need to learn to live in this toxic environment. It is all our fault, as others are not willing to claim responsibility for there actions, why should I. It is not my problem to fix the sick world, it is my responsibility to take care of myself. That may mean avoiding the "sick" family, a bunch of food pushers.
Some thing are up to me, and some are not. I am responsible for my opinions, my beliefs, my values, my motivations, my intent to act, and the like. I am not responsible for your reactions to me.
I think I will go through shafts down a lane. What do I know or care?