people are genetically different,have different bodies and different ways of converting food into energy. you can have fat healthy people, thin unhealthy people and vice versa. consistantly eating a nutritionally balanced diet is probably the best way to get some indication of your stable weight, what your body is actually supposed to be, this would help give an indication of the bodies 'natural' weight. i think a lot of peoples weight fluctuates,but i feel this indicates that their diet needs to be looked at and controlled and a healthy, realistic, stable weight maintained that would be beneficial for the long term future too. (slightly harsh in comparison to the convienience of the modern diet, though i would imagine that the uk diet followed during the 2ww would put a stop to britains rampaging obesity epidemic)