<<Disclaimer:  Verify this information before applying it to your situation.>>
 
I too would like to see more discussion of post-diagnosis weight gain.  My
pre-celiac weight was normal to five pounds overweight depending on how
careful I was about what I ate, and when diagnosed, I had lost 25 pounds, but
since going gluten-free, I have gained about 1 to 1 and 1/2 pounds every
month.  It's not as simple as "check what your're eating" because I eat much
more healthily now than before, and my spouse says I don't each that much
(and he's not a "big" eater).  I've asked to have blood work done to check my
thyroid (2 different doctors) and both times was told it was normal.  I am
very aware of the fat content in my diet (and try to limit it to 30 grams or
less a day), and I am very active in general, and go to an aerobics class a
minimum of 2x a week.  The weight gain is also in odd places -- places I
didn't gain weight pre-diagnosis.  I used to gain in the stomach and face;
now I'm gaining in the butt and chest.  It's more than just "what I'm eating"
to be sure.