I'm not sure I agree with your statement that the thin people you were eating with were "working at it". I think naturally thin people do not work as hard at it. It simply comes naturally to them, not making it work for them. I think that is one of the big differences between "us" and "them". (yeah, life is not always fair

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If you know them well enough and feel comfortable with this - ask them if they are working at being thin. And pay close attention to what they are really saying and then compare it to your attutides about eating.
I guess what I am trying to say is that what they call working at staying thin does not require the same amount of mental energy (or will power) that it does for those of us who have a weight problem.
For example - while they are eating half their meal and forgoing the chips laying next to their sandwich, does it require minute by minute consious effort not to eat those chips? Or do they simply decide not to eat them and then forget about them.
Even if I decide not to eat them, my chips would sit there on the plate yelling at me! And it requires constant effort to ignore them. I think the chips on the plates of naturally thin people simply do not yell as loud.
While I aspire to have the eating habits / attitudes of a naturally thin person, I don't kid myself into thinking that it will be as effortless for me as it appears for them.
