I wondered about this a lot.
I am tall & thin, just genetically lucky I guess, and my T is almost as tall as I am but definitely overweigt, and she seems to have a problem with it. She often gives comments on my shape (well, you ARE thin... you DO have a good figure... that kind of thing) Btw, I'm not anorexic and her comments are actually off-topic.
But I saw her reading a rather famous diet book once when I came in, and since then I wonder about it. I think she has a problem with my figure. Well, it's her problem, I know, but I feel a bit guilty about is sometimes...