After reading this, the phrase, 'natural size' stood out for me. I felt the need to express the fact that not everyone, specifically in FA, sees weight in this way.
Because people tend to rebound; after dieting back to their previous weight, people have come to the conclusion that the previous weight is their natural weight or the weight they were meant to be.
I can't see it this way.
I don't believe that wherever we happen to land on the weight scale can be described as our true weight, because our emotional needs are part of our nutritional requirements, if they are unbalanced, that can and does affect our eating and/or weight. This of course varies and it is not the only factor nor necessarily the most important factor, although it does seem to be in some more than in others, which maybe why some people lose weight as a direct or indirect consequence of emotional change or resolution.
If natural means, inevitable, then I do not believe that with so many stresses, strains, misdirection's and disordered ideas thrown at us that we can state with confidence that most of us are at our natural size.
Wherever we have landed is possibly just our current version of it.