This subject is very controversial in general. I’ve known people that have lost weight and kept it off in several mechanical ways. This includes people that utilize an initial period of severe calorie or food-group restriction (diets), eating only when you are hungry and only what you want to eat (the “listen to your body, it knows what is good for you” approach), and the drug (remember phen-fen?) and surgery routes. They all work. Keeping it off forever is the problem.
To do that, you need to totally change how you deal with food on a physical, mental, and sometimes emotional level. We are talking about a life-long and drastic changes concerning something that you have to do every day for the rest of your life to stay alive. Nothing else will work. No pill, surgery, special diet, etc. We are not animals that you can put into a cage that only have access to the foods that some research scientist gives us. We have to make FREE choices every day. For many people with a significant weight problem, for whatever reason (genetics, stress, inability towards delayed gratification, etc.), making the right choices FOR THE REST OF YOUR LIFE can be damn difficult.
For me, it took a lot more than a “just do it” attitude, and planning to burn more calories than I consume. It took and takes constant awareness, and asking myself WHY I’m eating each bite before I allow myself to take it. My motivation is much like Tom’s, in that I had limited choices. It was change or watch myself die.
My 2-cents.