Thyroid UK
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Can't lose weight - any supplements I can take to assist T4 to T3 conversion which might boost metabolism ?

I have had Hashis for 40 years, and had radioactive iodine after diagnosis. I am on Levo 125mg, get regular checks and tsh is ok according to the info on this site - but I can't lose weight no matter what I try - been the same weight for years although I've tried every diet going! I need to lose about 2 stone and am getting very depressed about it.Read that sometimes a selenium supplement can boost the conversion of t4 to t3 - in those that are deficient - and that going wheat free can also help. I asked GP about being tested for t3 and t4 levels, but although he did request this on the lab form ( I have a copy of the form so I know he did )the Lab DIDN'T do it! So where do I go from here - as until I know what my t3 level is, I am at a dead end, and all I can do is use nutritional supplements - hence this plea for any suggestions/ideas Anyone got any other ideas.... please!

15 Replies

This is a scientific explanation which may be helpful. With thyroid gland dysfunction it would appear to be a world-wide problem.

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I have the same problem and it just gets me down because whatever health problem you get they say "well if you went on a calorie controlled diet and lose some weight that could help". But it doesn't work as you have explained and I had Radio iodine years ago and that is when it started after being over active they made my thyroid under active within 8 weeks ,I think I made the wrong treatment . I really do sympathise with you but don't think they have an answer to it. Good luck


Thanks, Imelda - its good to know I am not alone .


same hear so if you find the answer please let me know


Hwbrand, T3 testing seems to be such a battle of wills, but recently when the lab ignored my Drs request to include T3 in the other tests, I got him to write a blood request just for the T3 - there was nowhere for the lab to go with that, and my T3 was tested.


thanks for that - I'll give it a go


Is so frustrating and demoralising when the weight just won't come off :(

I started losing weight once my iron, b12, folate and vitamin D levels were better. Any one of those being low seems to hinder the weight loss. Most recently it was vitamin D that seemed to be the magic bullet. I seem to get deficient very quickly!

Avoiding sugar is a must for me. I can eat 1500kcal and not lose weight if I eat any sugary food. If I avoid sugary food I will lose weight on the same amount of kcal.

That's just what works for me though but perhaps it's worth a try.

Carolyn x


I'm taking Vit D,B12, and Folate - but maybe I'm not taking enough - what dose of these works for you? I also added selenium which I have read boosts t3 conversion. Ah. addictive, but I am trying to cut it out, and avoiding wheat, but it's so sad that Thyroid disease is the "cinderella" disease and we are so ignored - thank God for this site!

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1000mcg B12 injection a day for week, every other day for a week, then every 2 days, for a few weeks, can decrease to 1 x a week, if ranges high enough or feel better. 5mg folate a day for 3 months, Vit D3 3000 to 6000 iu a day.


My Aunt is using T-Convert and is having good results.

See the link below for more info:)


Sounds very interesting Priscilla! Is it helping your aunt to lose weight?


She's only been on them for a month on and off as she's experimenting-and everytime she takes them she feels much better and notices that her clothes start to feel looser-hence the fluid stars shifting:)


Thanks for that-definitely worth considering I think :-)


I had radio iodine 22 years ago. I was so very down a couple of weeks ago. I am feeling MUCH better this week and I think it's due to a few changes I have made (thanks to lots of great advice on here). You might have already tried these - but this combo seems to be working for me:

Taking Levo at night - I had never done this before and though the first 2 nights were unsettled - I'm fine now

Gluten free - I've been GF for two years - changed my body shape completely.

Avoid grains - I avoid all grains as much as I can and try (stress TRY) to keep potatoes to a minimum

Try very hard to avoid sugar (fail miserably most of the time!)

Supplements:(there are loads - but they seem to work for me)

BioKult Probiotic (2 capsules in the morning)

Eskimo Brainsharp fish oil (2 capsules in the morning)

Triple Magnesium Complex 400mg

Selenium 100mcg

Co-Enzyme Q10 100mg

Solgar Vitamin B complex

Vitamin D3 2 X 5000 IU

I also have IBS and will treat that with L-Glutamine and aloe vera gel caps when I have to.

I also came off the contraceptive pill a year ago - and that helped too.

To be honest - I have had little professional guidance on this - but I have done loads of research and reading and checked with my GP (who knows pretty much nothing about thyroid conditions and goes by the numbers) she believes that dietary supps are pretty harmless - i.e. you get rid of what you don't need and as long as the doses are low the risks are minimal - I know there are other schools of thought on that.

By all means feel free to tell me what I'm doing wrong - if anything - but I have to say - I feel 100% better than I did two weeks ago - that was before the Magnesium/Selenium and the moving the Levo to night time.

A note on diet - I find that following a low sugar diet based around protein and veg suits me best. I avoid soya as much as possible. I'm no saint and I do struggle with my weight - but when I'm disciplined I can get to a size I want to be. Try adding a couple of miles walk to your day too - it helps me no end.

I truly believe that gluten/cheap flour, preservatives and corn syrup are the root of so many of the world's dietary issues. I would recommend reading these two books:

Sarah Wilson is also a thyroid patient - and her advice is great - her sugar-free diet is also YUMMY (I know - seems unlikely!). The GAPS diet was formulated to deal with mental issues, and I know that I can feel totally lost in the fog sometimes. The elimination part of the diet is daunting, and I've never done it. But Dr Campbell-McBride writes in an accessible way and stipulates that the full diet is fine for most people.

Very best of luck with all of it. Losing weight is hideous enough for people with functioning thyroids, but I think I've worked out what works for me, you have to try things and your body does change.

If you do one thing - just one - please try life without bread and pasta (even the GF stuff) - you will feel amazing within a week!

PM me if you think I can help


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Have you had your liver function tests run? A couple of my LFTs are raised, and I've read that that will block weight loss until it is corrected. Oh lawdy - if it's not one thing, it's another. I too cannot lose weight no matter what I do, but I'm going to give it a try. One caution is that you mustn't lose more than 2lbs a week if you have a fatty liver, although there was no real explanation given. I really dislike those advisors who throw out such statements with no reasoning to back it up. Does anybody know about fatty liver?


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