Thyroid UK

Digestive / intolerance issues to blame?

I've been tired and feeling lethargic and weak for years. Brain fog, loss of libido, memory problems, itchiness (mainly face and hair), voice problems, sweating, still have acne all over my upper body and face even in mid-20s too. I'm male.

TSH has gone from a consistent 0.9 over the years to 2.94 suddenly. I also had my cortisol tested for the first time ever - 105 (range starts at 166).

Blood tests were always said to be 'normal' and doctors blamed it on depression. Some things did flag up however which were all vitamin related.

I've been low in ferritin, Vitamin B12, Vitamin D and folate (not always at the same time). My folate has always been on the low end of the range despite eating tons of veg and my B12 is only now 350 after supplementation. I have always eaten a high meat/dairy based diet so it's weird that I needed supplements to reach that level. Ferritin and Vitamin D are fine now. Had a PA test and I tested negative for IF antibodies.

Maybe digestive issues are to blame or something else? I don't have pain or anything that would ring alarm bells but maybe...

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Positive intrinsic factor confirm pernicious anaemia. Go to for advice on PA, B12 and folate deficiency.

TSH >2 indicates your thyroid is beginning to struggle but NHS won't diagnose primary hypothyroidism until TSH is over range. TSH only testing exludes a diagnosis of secondary/tertiary (central) hypothyroidism. If you can't persuade your GP to test FT4 in addition to TSH you might want to order a hometest from Blue Horizon or Medichecks. Medichecks offer #ThyroidThursday discounts.


Thank you :) but with regards to instrinsic factor isn't it correct that presence of it confirms that you don't have a malabsorption issue??



No, positive intrinsic factor antibodies confirm pernicious anaemia. One could also have malabsorption due to other issues.


Sorry, just checked my results again - negative IF antibodies!

I thought the results showed that the intrinsic factor itself (which is necessary for B12 absorption I understand) was positive but it's not the case



The IF antibody test has a high level of inaccuracy, as much as 50%, apparently. You really will be better off discussing it with PAS forum.

If your IF antibody test really is negative it rules out PA and if you have B12 deficiency it may be due to malabsorption.


Thank you! Will head over there


Do any family members have autoimmune diseases?

You really need to test TPO and TG thyroid antibodies to check for autoimmune thyroid disease

You can have high thyroid antibodies and "normal" Thyroid function tests.

Low stomach acid can cause of low vitamins and low stomach acid is a symptom of autoimmune thyroid disease

For full evaluation you ideally need TSH, FT4, FT3, TT4, TPO and TG antibodies, plus vitamin D, folate, ferritin and B12 need to be at good levels

See if you can get full thyroid testing from GP. Unlikely to get FT3

Also perhaps ask GP to run coeliac blood test.

Private tests are available

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 be done as early as possible in morning and fasting. This gives highest TSH and most consistent results

Link about antibodies

Link about thyroid blood tests

List of hypothyroid symptoms

Low stomach acid


Thank you, a couple in my family have an underactive thyroid and maybe also something else as they are still exhausted despite having been on meds for years! I've been referred to an endo, will ask them :) thanks


If they have high thyroid antibodies then get them to test these vitamins, extremely common to be far too low. This usually indicates gut issues and malabsorption

Any autoimmune disease, look at strictly gluten free diet.

Most UK medics are disinterested in diet and vitamin connections. They might, just might test for Coeliac disease, but it's far far more common with autoimmune disease to have non-coeliac gluten sensitivity. (NCGS) As there is no current simple test for this medics don't consider it an option

You can be as ill as coeliac with NCGS. Don't even need to have any obvious gut symptoms.

Silent coeliac and silent NCGS are both massively under diagnosed.


Intrinsic factor indicates likely pernicous aneamia

Do you use aluminium or non stick coated or foil cookware ?

These are lethal to the gut and the body

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I do and I didn't know that, oh wow. Will look into alternatives


Only ever use stainless steel or cast iron or glass /pyrex ....Morrisons and Asda do good but cheap stainless steel pans

Do not be tempted by claims of ceramic etc ....avoid resturants and all processed foods only fresh fruit, salads , veggies, meat fish cheese that you prepare

No tinned goods or sauces etc unless you make it from scratch dont eat it .....i spent 2 yrs of utter hell in a wheelchair over 30 years ago solely thanks to use of aluminium cookware

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