In reply to DancingOnRock:
> Of course they're not. But as I've said many times. Some people can eat huge amounts of food and not put any weight on.
Because they do one of (or a combination of):-
1. Having a high basal metabolism rate, or one that speeds up to burn off spare energy by moving the body or raising its temperature.
2. Doing a *lot* of exercise (I've lost count of the number of skinny 17-18 year olds I've known through Scouting who have quickly got fat when they have started driving and thus stopped walking, running and cycling everywhere as they were prior to that).
3. Eating a lot but largely of healthy food. Put away a few kilos of salad and you're just going to spend a while in the loo, not get fat.
> The complex bit is the most important and vital bit to understand and just reducing the amount going in will not reduce weight.
Yes it will, *if you reduce sufficiently*. It isn't the case that reducing by 100 calories a day will cause a loss of a pound of fat (3500 calories for the sake of argument) in 35 days, it'll take more than that.
> Mainly because if you reduce what's going in, the body will self regulate energy expenditure to maintain its weight.
>
> Anybody who continually says eat less is disregarding how the system reacts when you reduce the energy input.
Nope, it is exactly what will happen if you bring energy in down below energy out.
> If it was a simple energy out is constant and if you reduce energy in then the mass reduces has missed the most important feature of the whole problem.
At no point have I said that, you're oversimplifying what I was saying. You have to reduce energy in below energy out by the required amount. Energy out will vary on a load of factors - exercise, how cold you are, and how fast your metabolism is going at that point. But that does not change the basic fact of the equation - if calories in < calories out you *will* lose weight.
Neil