I am 53, in the last few years have continued to gain weight despite not eating much, and going to gym etc. Last week I was told I had a 12.5 level of ....can't remember the initials, but it means I have underactive thyroid. This makes total sense to me, as it feels like my metabolism just isn't there anymore! I am also always tired. The worst thing is a big bloated belly. I really hate it and it is uncomfortable. I am due to see doctor on Monday, and presume that I will be given thyroxine. I just want to ask....does it help? I am very fed up feeling this way. Also, is 12.5 a high level? I got the info from the secretary at my doctor's surgery, because otherwise I would have had to wait a few days to even find out what the problem was. So I asked the secretary which of my blood test results had come back as not normal. I had gone to GP due to putting on weight despite lots of exercise, not eating much etc.