mystikmind2000: I don't know who told you that is a 'major' reason?? Didn't you learn from Sesame street that no matter how you move around five cookies on a plate, there will still always be only five cookies?
All the variables (such as the point you made) that reduce or increase efficiency - efficiency of absorbing energy from food and the efficiency of burning that energy, it cannot be separated from the laws of energy intake verses energy expended.
no idea what you are getting at but I'll explain in different ways:
Human body doesn't like to burn fat. It is simply not very effective. it is a reserve for body to use in last resort (okay. not the last last. that is reserved for body digesting itself to keep operational. like muscle tissue disappearance)
The body will try to run on sugars and other stuff first before dipping into fat reserves.
Therefore:
During the day it will not touch fats, instead it will increase efficiency in processing sugars. then you eat properly but everything in one or two meal. the body will restock its supplies of sugars and other stuff but it will be too much to handle at once hence it will go into fat.
which then the system won't burn as the system does not want to use fat.
metabolism is not a simple equation of energy input and output. it is not: i eat 1000 calories but i burnt 1100 so I lost 100 calories worth of fat. stuff does not work like that. depending on when you eat, when you burn stuff the same amount of exercise and food can be 1200 calories gain and 900 loss.
the amount of food is one thing. the quality of food is another. And when and how you eat is a major factor in weight control as well as health.
