No Weight gain

There is alot of information in weight gain with an underactive thyroid but i have yet to find anything on an underactive thyroid in people who can not gain weight.

My reasons for posting this are that i may gain some information on why i feel so ill some of the time and not gaining weight and its reasons could be a clue to wellness.

I am not underweight but if i am sick or cant eat for even a short time my weight can just fall off of me. Iv always had a thing that i wanted to be heavier but this never happened. I think alot of the way i think goes back to when i was very ill with crohns disease and i went down to five and a half stone. I was ill and looked ill, now i associate wellness with weight making a person look well. Obviously i know is not the case as many people are not well yet they can not loose weight due to their illness.

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18 Replies

  • I've always been underweight according to BMI etc but had a healthy appetite. Could easily drop or gain 8lb in a couple of days. Didn't gain after quitting smoking either. About 6 years ago I started to gain weight and was very pleased as it was evenly distributed and I had a lovely cleavage for the first time ever. I also felt fit and well and I think, looked both.

    Rapidly lost 13kg 3 years ago. A year later Hashi's and Hurthle Cell carcinoma diagnosed and BMI was 16. Post surgery gained a couple of kg but lost it when I started on levo. Cannot gain on Levo but gained 2.5kg when I came off it for a few weeks. Lost again when I resumed Levo and BMI 16 again, weight 48.8kg, height 5'9".

    I agree with you that weight can make a person look well. I don't like the gaunt look I see in the mirror.

  • I agree its that gaunt look that i dont want. I never lost or gained weight when on levo. I did loose some weight before hashi diagnosis because i had a swallowing problem but swalling returned once on meds. Not sure what my bmi is but i weigh 8 stone 10,1bs.Everytime i gat weighed i get depressed becasue i think i must have put some weight on this time....

  • Hi My Endo says that sometimes hypo symptoms can be the same as hyper This happened to me, when a private doc over dosed me without blood tests.Also there are several autoimmune conditions, also hormonal, related to absorption problems. pancreatitis, Caeliac and other inflammatory bowel diseases., gall bladder disease too. and diabetes.These are more common in people with autoimmune thyroid disease.

    Best wishes,


  • Thanks Jackie, I had some bloods tests done and getting results on wednesday, for caeliac, diabetes,other and acth test.

  • Hi That is good but Cae,liac disease often not shown on the blood test, or biopsy, then you need to be gluten free for 6 weeks to see if it is that. other colon conditions biopsies, colonoscopies. Most common is the Pancreatic enzymes. Specific stool test called faecal Elastase. can be done by GP. you will need to educate them though! Or Gastro. brilliant test, comes back fool proof and simple to read. treatment is enzymes 20 mins before any food.not a drug. Common condition. My Endo identified it , effects all my absorption , although other things that effect it too.

    so important for drugs. especially.


  • Thanks Jackie, what are faecal elastase and gastro tests done for

  • Hi Faecal Elastase done for the enzymes in the pancreas which absorb o intake, if low,shows they do not, common but needs treating..especially for meds.Gastro often needed ( unfortunately) for anything digestion, colon, bowel etc. All the bits , not liver or ,kidney really in the abdomen. They usually do colonsocopies and often gastroscopies, both scopes, simple, just to check what is happening.usually biopsies of anything odd too


  • Good but remember the caeliac disease ,test often does not show it I know this from a riend`s experience but also, my Endo published a paper on i in the BMJ last year.


  • Hi, I would think it's more likely the Crohn's disease is the issue with you finding it difficult to gain weight. Even though you've recovered from the very serious period you had with it it is an illness that stays with you for life and needs to be kept under control as much as possible. Do you have any other symptoms at the moment?

  • I get many symptoms of hypo, lethergy, brain fog, cold and heat intolerance, memory problems.My concerning symptoms are what worry me the most, I have episodes when i feel very unwell,dry mouth,nausea, massivebrain fog and feel like my bowels are paralysed, not constipated at this time. The main feeling is of unwellness.

  • Hi

    I have ulcerative colitis so have a similar problem with weight gain to yourself and am on 100mcg of levo along with other meds for uc. I also cannot gain weight but then have a very poor appetite at times when feeling very unwell so I think it is the crohns that is affecting your weight as the uc is with myself.

    Best wishes to you.

  • Thanks norwood1, yes maybe its the not absorbing nutrients properly. Iv been lucky with the crohns in many ways since i was ill with it. That said its still a chronic auto-immune disease which must impact at some level

    Did you have to have surgery for colitis?

  • Hi

    Yes i agree with the body not absorbing nutrients etc and it is a horrible disease and makes you very very unwell at times. No i have not had a surgery, my uc is controlled with medication and i see a consultant regularly and have colonoscopies regularly so I am lucky in comparison to others. Problem with an autoimmune disease is that it leads to other parts of the body also being affected at any time as I found. This site is wonderful as you get really good advice and opinions from others which helps greatly. That said it does not really answer the weight issue but I put it down to my uc and my body not being able to absorb or take in all that it needs. I also supplement with vitamins and have B12 injections which I hope you also have as.

    Best wishes

  • Iv never had B12 injections and dont take supplements. Mcmh blood test came back abnormal, doctor did not knowledge it but when i rad about it, it suggested annemia yet my hb is normal.

  • Why dont you ask your GP/surgery for a print out of your blood test results and post them on here where you will get a lot of advice. If you are anaemic, which your bloods obviously showed as coming back abnormal your GP should be doing more and giving you folic acid/B12 injections/iron in my opinion as these will help you an awful lot and make you feel so much better in time. Normal results dont always mean that just because they say normal are in the right range for some and need to be questioned.

  • I have the exact same symptoms as yourself yorkshiregirl44. I don't feel sick all the time just know and again. Just so fed up of feeling 86 when I am 46 and not losing weight even when I watch what I

  • Bear in mind that not all weight is the same!

    Hypothyroid people can gain weight because of, for example, the increased myxoedema. But at the same time they can lose weight due to loss of muscle mass. One process might have more impact than the other - and it is not a foregone conclusion.


  • I too have trouble gaining weight and look gaunt however when I went to my GP he said everything is ok but I know its not. Any advice on what I can do will be greatly appreciated.


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