Life is guaranteed to eventually provide any normal person with something to feel guilty about. So guilt happens. For whatever reasons, every healthy adult has some guilt feelings about things that he or she probably should not feel guilty about. And, as you might guess, some people manage to make a subconscious connection between their guilt and the shape of their bodies. When this happens they make themselves overweight to punish them for their guilt.
That may sound crazy but I am speaking about the subconscious mind. It is the subconscious mind that is in the driver's seat and that part of the mind doesn't do "logic' well. I am always amazed by the fact that there were so many masochists. Perhaps people could learn from their mistakes and stop torturing themselves. Making a mistake and NOT doing it again is wise. Punishing oneself again and again makes no sense.