Thyroid UK
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loosing weight with hypothyroidism?>

Hello I'm Clare

I was diagnosed just over a year ago now, and my levels are good. Taking 100mg levothyroxine. I have too have a small op, for another problem been put on the waiting list so I'm really paranoid so i've decided I need to loose some weight. I want to eventually loose 3 stone but I'm hoping to loose a stone over the next two months.

Did you find it hard to loose weight with the condition?

Thank you


12 Replies

Absolutely! I seemed to go up about two stone once I was on Levothyroxine, and have struggled ever since to lose it. Increasing exercise helps, but as I have low B12 and fibromyalgia as well it makes it hard to do enough. Good luck.



Hi! It is tough but not impossible to lose weight but of course we are all different so really it is a case of try it and see. I have a T3 level that is 3.2 (3.6-6.5) and I am hoping to be prescribed t3 soon as clearly I can't convert T4 to t3 efficiently. I have put a stone on since first being diagnosed. First time I have gained weight in 14 years. But it is coming off slowly but I eat very little. No alcohol, bread, sugar, fat etc. I also exercise 6 days a week. it's very hard but I Am So determined to do it. Keep strong and positive. Eat a healthy diet. Fruit, veg and lean meat. No gluten etc and it should all help. Sadly there is no magic pill to help with the weight loss. Good luck! Xx


Sorry to be a wet blanket, queridalady, but your weight-loss programme may back-fire on you.

For a start, not eating fat is a very, very bad thing. It is not healthy. Your body needs fat. It needs cholesterol. Without cholesterol your body is unable to make certain hormones, and without them you will get fat! Besides, eating fat does not make you fat. On the contrary, research has shown that those that eat the most fat lose the most weight. I know it is high in calories, but you need calories when you are hypo. Forget the calories in vs calories out mantra, it just doesn't work when you're hypo. You need fat, protein, fruit and veg, and certain amount of carbs. We hypos do not function like other people.

As to the exercising, all that exercising is probably what is keeping your T3 so low. Exercise uses up your T3. In someone with a normally functioning thyroid, the gland can compensate for the hormones used up. You cannot. You are using them up and leaving nothing for other bodily functions such as metabolism.

Exercising also uses up your calories, and it doesn't sound as if you're getting enough as it is. I know you're going to tell me that that's the point! lol But, as I said, when you're hypo the rules no-longer apply. You need calories for every bodily function, such as breathing, digesting, blood circulation, etc. You also need them for your conversion of T4 into T3. If you cannot do this then you are going to get more hypo and thus put on more weight.

And quite apart from all this, the weight you've put on is more than likely water-retention (that's what we hypos do! lol). We fabricate a substance Under the skin called Mucin, which holds water. No amount of dieting or exercising is going to change that.

What you need to do - and I know it's not easy - is to increase your T3, by whatever means. Then you will be able to lose weight more easily without torturing yourself.

I put on so much weight when I started levo - although I've never been thin - and even more weight when I went onto Armour! It just didn't suit me. I don't know exactly how much weight I put on over those 10/11 years because I stopped weighing myself when the scales tipped 120 kilos! It was just too depressing, and there was nothing I could do about it. Until, that is, I went onto T3 only, a couple of years ago. I just couldn't convert and the T4 made me ill - not saying that's your problem! Just telling my story. Anyway, on T3 my levels have risen - as you would expect them to - and the weight has mostly come off, about 40 kilos I'm guessing, need to lose about another 10, and I don't diet or exercise. I eat what I want, when I want it, and how much I want - although I don't have an enormous appetit - and I eat lots of fat. Because I like it and because I'm desperately trying to raise my cholesterol! Exercise is difficult for me because I've lost a lot of muscle strength whilst being horribly hypo and having low growth hormone.

So, tell me to mind my own business if you like! But I hate to hear stories of how people are struggling to lose weight when it's usually the doctors fault for keeping them hypo. Hope you get your T3 soon.

Hugs, Grey

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Wow, thanks Grey for your pretty negative and critical reply. This is the first time I have really replied to someone on the forum and I did so because I understand the worry and concern and I wanted to come back with some comments that included some positivity. Like I said, everyone is different. I have always had to eat a very healthy diet to control my weight and I have been 9.5 stone (5.7') for the last 14 years since having my daughter. Not by starving myself or counting calories which I have never done but by making wise choices and exercising. I don't exercise because I have to, I excerise because I love it. It is a great stress reliever and in times when I have not been able to yoga or play tennis for whatever reason I have still tried to walk in the fresh air. And before any assumptions are made, I am a mum and work full time and my husband works away during the week so it is a challenge to fit in all the things i need to do, myself being the last priority as our daughter comes first. I perhaps made too much of a sweeping statement regarding fat and should have been clearer - apologise for that. I should have said bad fat. I eat coconut oil, olive oil, butter, nuts and seeds etc. I totally agree with you that a hypo body is very different to what i have known and to deal with before and I am researching and learning all the time and I am adjusting my lifestyle accordingly. Whilst you say that my exercise regime may backfire on me I can tell you now that it won't. I am a sensible woman and so far by eating well, and exercising in a manner in which I love, I have lost 5lbs in 4 weeks and I am sleeping better and feel more positive which is a huge help when we have to struggle with what we do with hypo. I totally appreciate your comments and respect your experience but when a member mentions that they are paranoid that they won't be able to lose weight then surely it is better to be a little positive than tell them how bad it is going to be? Just my opinion of douse. I am desperately hoping that I will be given the opportunity to try T3 and further hoping that it will help me but I can't just rely on that. I have seen a nutrionist experienced in thyroid issues to get there advice because my food choices at the moment a req


Wow, I'm sorry you found my comments negative. No negative intention, I can assure you. Just facts. Fact 1) you need T3 to lose weight. Fact 2) you have no T3! Etc, etc.

I actually thought that telling you my story was positive, because I've done it. I've succeeded. 20 kilos since Christmas. But...

As for critical. Well, you hear what you want to hear... I wasn't criticising you. I was trying help. Silly me!

Anyway, I wish you well for the future, and all that.


Weight gain when hypothyroid is a very common question. As our metabolism has lowered due to being hypo (low) it is very difficult to lose weight until we are able to raise our metabolism again with thyroid hormone replacement.

This is a link and there are some books within which may be helpful.

If the GP keeps your TSH at too high a level it will be difficult to lose even if it is within the 'range' -. From your comment above, I believe you are feeling good on your dose of levothyroxine so it might be easier for you and I hope so. Weight gain is usually one of the first clinical symptoms of hypothyroidism and if not on optimum medication our metabolism isn't raised.

When you have a blood test for your thyroid gland: if you take your medication in the morning, don't take it before the test, take it afterwards as it can skew the levels. If you take it at night, miss this dose and take after blood test. Always get a print-out of your blood test results for your own records and so that you can post if you have a query. It must have the ranges too as labs differ.

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quite limited as eating gluten has damaged my bladder (who would have known it) so I have to consider that to. But I will not give up….I will find a way to help myself no matter what it takes otherwise what is the point? You have clearly had a tough time and it shameful how our health service don't help thyroid patients more than they do. Thank goodness for places like this where knowledgeable people share their experiences. Thnak you for that. However it clearly seems that my experiences and not welcome so I will stick for easing in the future! :)

Good luck Clare…I wish you well! xx

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Thank you for the replies!

I've been told my levels are in normal ranges but I do feel tired a lot but I've been told that's probably my gynaecoligical problem. That I'm having the op for. I have lost five pounds by walking a lot and I've started to make all my food from scratch and make my own snacks. But I'd love to be a size 12 again :). I've cut out fizzy drinks And chocolate. All I have to do now is walk past the donuts in the shop. Then I hope I'm on to a winner :)

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Hi. I'm newly diagnosed over active, and have put on loads of weight before being diagnosed.

I may be being a bit think.... But what exactly is T3 & T4 and how do I find out what mine are?? Are these in the blood test results???


im with you-diagnosed in august,and the gp did not tell me ANYTHING at all about this condition-just asked me did i want to go on levothyroxine,or did i want to leave it a while and see how it goes!!?! im totally confused reading about t3 and t4..are they medications or thyroid readings? ive literally been told nothing about hypo,just that i have it,and to keep taking the tablets (only 25mg per day,which is the lowest ive read about) and to come back in 12 months. Im losing no weight,and still having bouts of depression and anxiety. Can I ask for T3 instead of Levo?


Just to let you guys know. I've lost half a stone!! so happy.


Well done :-)


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