Thyroid UK
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Constant weight gain, low calories to maintain weight. Need input please!

Hello Everyone

I've recently been diagnosed with hypothyroid and as such been given Levothyroxine for treatment.

I have a ongoing problem with Prolactin (I still have a Prolactinoma) and take Cabergoline on a weekly basis.

My reason for posting here is because for the past 5 years I have had an on going weight issue, and my issue has gradually been getting increasingly worse despite higher efforts to counter this.

Cutting a long story short, bringing it up to the point of starting Levothyroxine (due to lack of energy, weight gain) about 5 months ago I have seen correlation between my weight increasing even more dramatically than before - now I have to be so strict to even maintain my weight and a day or two of not being strict will quite easily add 2-3lb of weight onto me without even going over the top - and it isn't removable without drastic calorie restriction (so it basically isn't tempoary water weight gain from increased intake).

I wasn't expecting instant weight loss, but assistance with it was desired. I am currently on about 1700-1800 calories per day, weigh 210lb and am 5'5''. I am balooning up constantly and I am quite unsure as of what to do next.

I have read reports on the internet where Levotyhroxine has made them gain weight... and I am feeling the same.

I feel incredibly fat right now, and over the past 5 years all I have ever tried to do is lose weight (fat), yet actually ended up about 50lbs heavier at this point. My eating habits have actually decreased as weird as it sounds, because with each year going by the caloric restriction has had to be more severe.

Anyone chip in and help? I've spoken to my Endo and Doctors and to be honest they don't really give my much hope - just saying as time progresses things will change and it just doesn't and for the past 5 years things have got much worse.

Hoping for some advice/experience here.

Thanks for reading :).

6 Replies

Hi there I have just read your message and I am in exactly the same place as you, and have just made appt to see go. I am at my wits end as I just keep gaining weight. I thought I would just drop you a quick line to let u know you are not alone and I will be very interested to see the help or advice you get, as I feel like no one believes me when I say I am not stuffing my face..u only have to look at my partner to see we eat healthily. All the best x


Hi Frustrat3d & tuesmum,

I too am in the same place as you two! I am frightened to eat anything much, as I know it will add a few pounds, that will take weeks to try to remove. I think some say it's because we are not on enough Levothyroxine, but if I take a higher dose I get the symptoms of being overactive I am on 100mgs, I was on 125mgs. I will be interested to see your replies, hopefully someone can help us to resolve this very distressing problem x


Hello there,

I had a 6/8 thryroidectomy 13 years ago, I became hypo and have been on a steady 125mgs of levothyroxine for 10 years.

OK, so I will share my experiences with weight with you.

When I had my operation I was 9.5 stone (I am 5'8") and a size 10 - 12. I ate what I wanted (I had graves disease before my op). My level weight is 10.5 stone, that's my "happy" weight and I'm a size 12 on that weight. Today I'm 13.5 stone and a size 16. My heaviest was 14.5 stone.

Over the last years I've read just about every book and this is what I live by:

1. In order to maintain a healthy weight I have to eat 500 calories less than someone my size. I have to be VERY organised about my food in order to achieve this.

2. I have to do some sort of exercise EVERY day.

3. If I am on a diet I know that I need 500 calories less than the person my starting weight. In order to ensure that I facilitate any diet correctly I join a club that works for me that has plenty of "free" foods, so I can embrace fresh ingredients (aside from the do not touch list that works against my thyroid) and being part of this means I have support.

4. I try and limit stress.

My weight has recently ballooned to 13.5 stone, due to personal stress my life stopped; I stopped planning my food, I stopped going to the gym and here I am on a diet again having put on 3 stone in 3 months. But, it's manageable and I will see those happy weight numbers again.

I recommend that you read up on the facts about your thyroid from a health and diet perspective, knowledge is power and it really is power. There are some great books out there.

Finally, don't worry about it! It will work itself out.


I wonder if you have tried avoiding gluten. I am on gluten and dairy free to hopefully reduce my anti bodies but I am now losing weight. Had been the same weight since hypo was first diagnosed 7 years ago. I have now lost 8 lbs over last couple of months. I do not count calories, but not eating gluten found in cakes, biscuits, sauces, pasta etc seems to reduce calories anyway. I eat fruit and salad veg to "fill up." Hope you solve your problems


Have you any recent blood test results you would be willing to share with us? You may be undermedicated even if the doctor says your results are normal.


Can I ask how tall and how old you are? It might be that 1700 kcal is too much. I'm 1.55m and 38; to maintain this weight, under ordinary circumstances, I need to eat about 1500 kcal.


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