I think in the long run there are a lot more benefits to just been within 10-15 pounds of top shape. It means you can pretty much eat what you want and relax a little e.g.holidays, eating out etc but it also means that most the time you can look presentable when you need to, again an example would be being able to go to the beach without looking like a whale. I've been 40 pounds overweight without even seeming or realising it and from where I'm at now I can see the clear negatives to carrying that amount of weight.
