weight gain and hyperthyroid: thoughts please... - Thyroid UK

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weight gain and hyperthyroid

19 Replies

thoughts please - this is the first time I've posted on here. I was diagnosed as hyperthyroid in feb this year - I had gradually been putting weight on and was constipated - my blood results were - TSH - <0.01, free T4 - 24.9, anti-TPO antibodies 1.0, ferritin 243, caeruloplasmin 0.27. I was put on carbimazole 20mg. I was advised to join slimming world , and exercise - I had been doing this for months and loosing very little weight. a few months later I was advised to reduce my carbimazole to 10 mg as my liver enzemes were too high. I have got a personal trainer go x 2 weekly ( struggle to afford to go) and have now only lost 1/2 stone since feb - my diet is excellent. I am 3 stone over weight.

my bloods last week were - TSH - 1.61, T4 - 6.3, T3 - 3.7, vit D 39. I can see I've now gone hypo with the carbimazole. ive reduced this to 5mg.

Any thoughts would be gratefully received, as I'm desperate to loose weight and don't understand why I was gaining when I was hyperthyroid. My endocrinologist - just tells me to exercise more and keep going to slimming world.....

19 Replies
greygoose profile image

Sorry, but it's very difficult to understand what's going on if you don't put the ranges with the results. Ranges vary from lab to lab, so you always need to add them.

How were you diagnosed hyper? Just by the TSH? Your FT4 doesn't look very high. Were Grave's antibodies tested?

Slimming World really isn't the best way to lose weight because it's based on low/no-fat, which isn't very healthy. The body needs fat. Your FT3 now looks very low - but we do need the ranges to know for sure - in which case, you should not be doing strenuous exercise. But, endos - and doctors in general - know little about thyroid, and even less about nutrition!

in reply to greygoose

Sorry ranges are tsh (0.35 - 5.50) t4 (7.0 - 17.0) free t3 (3.5 - 6.5) free t4 (7.0 - 17.0) anti- tpo antibodies (<9.0) I was told it was diagnosed by the TSH and the T4 he said it was not caused by an autoimmune disease.

My personal trainer has me eating healthy fats - nuts/avocados/rapeseed oil etc

Madsokri56 profile image
Madsokri56 in reply to greygoose

Low carb diet isn’t good for thyroid

in reply to Madsokri56

Where can I find out what I should be eating for the thyroid please?

GraceLucy profile image
GraceLucy in reply to Madsokri56


amysmakeup profile image
amysmakeup in reply to Madsokri56

Why is this? I would be so interested to speak to you about it : )

in reply to amysmakeup

From reading I’ve done and comments above - certain foods help the thyroid heal & function better - but not really sure what they are !

Madsokri56 profile image

I’m hyperthyroid on 10mg per day of carbimazole and putting on weight too getting terrible panic attacks and heart palpitations want to hit my head against a wall when I asked how long I would have to take carbimazole my doctor said 9 years wtf I have a goitre and found out my condition after being unconscious and ending up in emergency at the hospital after my own body nearly poisoned me to death

SlowDragon profile image

Surprisingly common for early stages Hashimoto's misdiagnosed as Graves' disease. Your symptoms suggest Hashimoto's rather than Graves

Did GP or endo test TSI or TRab antibodies for Graves' disease?

If your endocrinologist thinks Graves or Hashimoto's are not autoimmune you need to find a new specialist

Thyroid Uk has list of recommended thyroid specialists here in UK

Have you had ultrasound scan of your thyroid?

Assuming you are in Uk and Vitamin D is measured in nmol - this needs improvement to around 100nmol with vitamin D supplements

You also need B12, folate and ferritin tested

For full Thyroid evaluation you need TSH, FT4, TT4, FT3 plus TPO and TG thyroid antibodies and also very important to test vitamin D, folate, ferritin and B12

Private tests are available. Thousands on here forced to do this as NHS often refuses to test FT3 or antibodies


Medichecks Thyroid plus ultra vitamin or Blue Horizon Thyroid plus eleven are the most popular choice. DIY finger prick test or option to pay extra for private blood draw. Both companies often have money off offers.

All thyroid tests should ideally be done as early as possible in morning and fasting. This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, GP will be unaware)

Both Graves and Hashimoto's are often linked to leaky gut and gluten intolerance





Marz profile image
Marz in reply to SlowDragon

Oh dear - it does worry me that there seems to be more and more people with a questionable diagnosis ...

in reply to SlowDragon

thankyou I will follow those links up now.

im very confused !!!! my T4 originally was high and my TSH was low - then after taking carbimazole my T4 is low and TSH in normal limits - does this not mean im hyper and because of treatment ive become low?

My endocrinologist said I didn't need a thyroid scan, when I originally questioned him, why I hadn't had one - in October when I see him again I will ask why. I've not had TSI or TRab tests done. I did have anti-TPO antibodies taken - 1.0 (normal range <9.0) and because of this was told I didn't have an autoimmune problem causing the hyperthyroid

Is there a list of nutritionists/dieticians I can go to for advice on thyroid problems, leaky gut and gluten intolerance please?

SlowDragon profile image
SlowDragonAdministrator in reply to

Would suggest you get full Thyroid and vitamin testing via GP or privately. Especially retesting TPO and TG antibodies

Endocrinologist should have tested TSI or TRab before starting carbimazole

Getting testing asap, otherwise you are completely in the dark

Improving vitamins is first step. Trying strictly gluten free diet next.

Likely need to reduce carbimazole further.

Link about thyroid blood tests


Link about antibodies and Hashimoto's




please email Dionne at


For list of recommended thyroid specialist. But always get full testing before seeing any consultant. Come back here with new post once you have results and members can advise

in reply to SlowDragon

thankyou very much, will do as you advise x

in reply to SlowDragon

I’ve been confused by your post - after doing some more reading wondered if you’d mind explaining- I had put in my post that my autoimmune antibodies were negative- how can I have hashimotos - my understanding is that the blood test needs to be positive to have an autoimmune disease?

Also please can you explain why a thyroid scan is necessary - I want to go armed with reasons when I go back to the consultant.

Many thanks

SlowDragon profile image
SlowDragonAdministrator in reply to

You only seem to have had TPO antibodies tested. You also need TG antibodies tested, but NHS usually refuses to test TG antibodies if TPO are negative

High TG antibodies are not specific to one problem


Your FT4 is EXTREMELY low - you are needing reduction in carbimazole

Insist on having TSI or TRab antibodies tested to definitely confirm Graves' disease

And/or ultrasound scan of thyroid to check for Hashimoto's disease

Strictly gluten free diet very often helps both Graves or Hashimoto's

Ask GP for coeliac blood test first and to test folate, ferritin and B12

If they are unhelpful then you may be forced, like thousands on here, to test all this privately

But see if GP is amenable to testing first

Your vitamin D is too low and needs improving to around 100nmol

ZRachel profile image

Unlike you I lost weight (4 stones actually ) before being diagnosed with Hyperthyroidism, honestly I was thrilled. I started carbimazole in November and put no weight on until March. I am now a stone heavier but have been told I do not look as ill as I did. In my case undiagnosed Hyperthyroidism led to osteoporosis and I have 4 broken bones in my back. A combination of carbimazole and opioids is a recipe for bloating and constipation. Advice is to switch to soya and gluten free neither of which I like. However I have maintained only a 14lb weight gain by eating healthily, plenty of fruit plenty of fibre and at least 2 litres of water a day. Actimel yoghurt drink is great for bloating and fibergel sachet stops constipation. I believe Hyperthyroidism can be managed. Good luck!

in reply to ZRachel

Thanks for the advice x

GraceLucy profile image

I've been up and down with hyperthyroidism since 2014 and am 27. Now on 5 mg of carbimazole and have surgery planned for the Autumn.

I've had to change my diet. I have smaller portions in general and have moved to a 'soft' keto diet. i.e. I avoid all white carbs and stick to meat/fish and lots of veg. I'm much less bloated and am relieved I haven't put on loads of weight like I did when I first was treated for Hyperthyroidism. It's so difficult though as when ever I have an off week (e.g. a holiday) I feel it takes me longer than others to shift weight. But things could be worse!

Good luck!


in reply to GraceLucy

Thank you x

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