Being overweight myself I have spent a great deal of time examining why I succeed and fail to lose weight at different times in my life. Two things immediately come to mind that help and they are having a strong motivator and having people who genuinely seem to have a vested interest in my success. The first one is easy but usually temporary, the second one is much much more difficult to achieve, mostly because of my own perception of the world and the other people I encounter in it.