I've had an underactive thyroid for about 12 years, and haven't managed to lose any weight. Have just spent 3 weeks in an obesity centre, and my total loss was 'nil'.
While I was there I had an x-ray and a scan, and have found out that I've got gallstones. Looking on the internet, they're more common if you have an underactive thyroid as the metabolism slowing down causes problems with digestion. There also seems to be some question that they can interfere with converstion of the inactive hormone to the active hormone.
So, anyone else having problems losing weight with an underactive thyroid and found they have gallstones, and then magically managed to lose the weight after having their gallbladder removed?