I've had underactive thyroid for 9years gp said my levels are fine don't eat hardly anything still put on 3 stone can not shift active all day any one help
Weight gain : I've had underactive thyroid for... - Thyroid UK
Weight gain
with the little information that you have given I would say your gp thinks your levels are fine but I would say they are not if you genuinely attempting to lose weight and none is coming off and you are actually gaining weight then you are undermedicated and chances are whatever you try it won't come off but if you had your latest blood results I could have said for definite.
Basically though you can lose weight but you need to be well medicated to be able to and with that I mean a TSH of 1 or below and a T4 level high in range and you would need to exercise (and I mean something like a firm 30-60min walk several times a week or similar no more strenuous) be careful with eating hardly anything you don't want to go into starvation mode and gain even more.
once well medicated you would have to find a diet that works for you, I'm successful with calorie counting having lost 3.5st I want to lose more but taking a break as it can become quite obsessive if not careful, others on the site have been successful with the paleo diet, weight watchers, slimming world, etc. everyone is basically different.
good luck I hope you will find something that works for you.
Do post your latest thyroid blood test results so we are able to help you more. Could be you are not converting the T4 into the ACTIVE T3.... So you need to see the results of the TSH FT4 FT3...
How are your levels of Iron - Ferritin - Folate - B12 - VitD....if these levels are not optimal then conversion will be slow....
Have you tried the 2 day Diet - thetwodaydiet.co.uk ?
Unexplained weight gain can be the first symptom of hypothyroidism and it can also be due to not be on an optimum level to raise your metabolism.
This is a world-wide problem which seems to be ignored by the medical profession completely and lay the blame on the patient.
There is sufficient explanation in the first page to discuss with your GP:
web.archive.org/web/2010032...
Also, always get copies of your blood tests with the ranges for your own records and so you can post for members to comment.