A further update!
I started levothyroxine treatment at the beginning of July, 2016. I weighed 18st 7lb and was miserable, ashamed, exhausted, in constant pain and unable to eat more than 500 calories per day without gaining weight. It was a struggle just to get through each day.
My GP has a lot of thyroid patients. He ordered a whole battery of blood tests for all kinds of possible conditions, and when the results came through he called at my home to tell me my thyroid function was seriously compromised and that I must start treatment immediately.
I started-out on 100mcg. Over time this was increased to 200mcg. I'm still tired and my sleep is all over the place but I feel much better than I did before. I have more stamina and my brain fog has lifted considerably. Not 100% recovered yet, but maybe 90% considering my age (62).
Best of all from my point of view I've now lost a total of five stones. Very good progress in a ten-month period. I'm so happy about this. Only 3.5 stones to go now to my 10st goal, where I maintained without regaining for seven years.
Please don't give up, people. When the right dose of levothyroxine has been determined, and when you find the right diet (for me it's HFLC, with a few occasional treats), miracles may well start to happen. I am vegetarian which makes low carb a bit trickier than it is for meat eaters but it's not that difficult. My advice is to quit sugar or keep intake to a minimum. It's no good for people with thyroid disease. Indeed it's not much good for people, without!
I will continue this controlled but not severely restricted way of eating indefinitely. I was huge and as overweight people will know it's horrible. When you're struggling to cope with a multitude of hypo symptoms at the same time you often end up in tears.
I am so grateful for my progrss so far. I'd been ill and undiagnosed for years - by no means unusual - and had put my symptoms down to my age, menopause, fading hormones, lack of exercise, blah blah. Now I have a diagnosis and a treatment. I feel lucky to do well on levo.
Don't give up at the first hurdle. Persevere!