This will make a great hub idea. But, the quick of it is from my experience is you got to think like politicians and some governments. Simply, deficit spending and residual cost overruns. Get those down and you will lose for sure.
In other words it takes 3500 calorie deficit for one week to lose 1 lb./week. Or, a deficit of what is normal now of -500 calories per day. That can be from diet/nutrition or exercise. Recommended weight loss for long term positive results is about 1 - 2 lbs per week. That rate is desirable for health and for sustainability of maintaining the NEW lower weight. OK, that explains the deficit spending.
Residual costs overruns comes from increasing the metabolism. Doing this through food choices, exercise and healthy habits assures a constant burn of calories, even though they may be low. Think of the space shuttle flying. The exercise is the take off, but the miniscule thrusts to maintain directions and momentum continues to create calorie burn - increased metabolism.
I weighed 225 at 5,10" (2005) with what is called a small frame according to my wrist measurement. When I was 18 (1972), I weighed on a good day 130. Today, I'm happily at 165.
Oh, remember the gov't is sneaky too. When you lose weight real fast or use some aids or drink diet sodas (aspartame) you trick your brain, confuse it, and well the body kinda' revolts and begins to store fat. Doesn't weigh a lot, but sometimes muscle loss occurs too. Aha - weighs more therefore weight loss.
I don't know if that helped or not. It was a late night :)
Just for a fun theory read my hub - Be a Writer! CONNECT the Body, the Mind, and the Spirit and LOSE weight! http://tsmog.hubpages.com/hub/LearingStepstowritin... It is a satirical article I came up with after watching too much Saturday Night Live. :)