The problem is not the diet, but the inability to follow the damn diet. Hunger, cravings, desires, emotions, un-named pressures, all push us off the diet, food program, prescribed restrictions. Until we understand and treat these issues, obesity will remain long term.
For some of us, this started in childhood. It is a issue that we do not clearly know the cause, perhaps the cause is absence of emotional support, or absence of physical support, we were placed in a no win situation, and we ate to resolve the feelings, (high BG helps reducing feeling) or just to survive. This habit, behavior became "burned in" - epigenetically, and now we live with this problem.
When we read Jonice Webb, Running on Empty, it becomes apparent that this is likely the problem, but it is an unknown unknown that is driving our decisions. Now it is necessary to use a shotgun approach to identify the problem or rather the solution that works. Total reloading of the operating system. Reboot with a corrected program. But where are we to get the new "corrected" program from? Not from religion, not from the philosophers, not from the government, or psychologists? So where? Well, nobody has figured that one out yet, but many preach bits and pieces, and to every one preaching, there is much opposition, often more than are advocating any position. So the solution is reloading piecemeal, one belief, one emotional response at a time and we are soully responsible for our choice or decision.
But which unknown unknown? And we live in an environment which is beyond our control and then when the obvious solution does not depend on us? Now what? It is the unknown unknown that must be identified and relieved. Or does the obvious solution destroy all that we have built up to this point in our life? Or we need a change of environment. Or do we not have the required energy to implement and carry out the solution? Money always has the veto also. So there is no solution.