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Hypothyroid and also maybe b12deficient

Hypothyroid and also maybe b12deficient

Hi , I have hashimotos and am on thyroxine 125mg and t3 10mg . Doses have changed over the last twelve years since being diagnosed by Dr Toft . I have never been symptom free and just wondered if I might be vitamin b12 deficient , I know that can be quite common with hypothyroidism . My b12 reading is 392 reference range 180 - 2000 my doc says my results are normal , so I just wondered why then do I still have all these symptoms . Has anyone else got a vitamin b12 defienciency and also hypothyroid . Any replies would be greatly appreciated

6 Replies

Well despite your being 'in range' for your B12, it is seriously low. I have been reading a book about Vitamin B12 deficiency and Pernicious Anaemia and the advice is that we should aim for a level of 1,000 or above. (Excess is excreted in urine) we cannot overdose. Apparently, if we are below 500 (another article) we can develop dementia. We can supplement our B12 sublingually but it must be methylcobalamin and not cyanocobalamin. methyl is superior.

If you order from Amazon get small commission. I also read that Betteryou supply good quality supplements.

If you are not symptom free your thyroid medication needs to be looked at. Get a copy of your latest blood test results with the ranges and post on a new question. If you are due a new blood test, make it as early as possible and don't take your medication until afterwards. If you take medication at bedtime, miss this dose and take after blood test.

If you haven't had a Vitamin D, iron, ferritin and folate ask for these too as we are usually deficient.

I am well now and it has taken a little while but sometimes we have to suss out with the help of the forum what may suit us and bring back recovery.

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Shaws, is ferritin the same as iron? (Doc said it was). What are the best ranges for these?


Ferritin is a measure of your iron stores, so it isn't exactly the same as serum iron. Doctors often treat the two as being equivalent though.

The problem with relying on ferritin as a measure of iron in the body is that it can be elevated if there is inflammation in the body and thus gives a false picture. Someone with lots of inflammation could be seriously short of iron, but the ferritin may suggest that everything was tickety-boo.


The above link should tell you all you need to know and more about B12 deficiency. You could also type B12 into the search box on the green bar above and have a read of what comes up. Most people are seriously under - as you are - but sadly GP's have little clue as to how to interpret results for B12 or other vits and minerals....

The T4 medication will not convert into the ACTIVE T3 if you B12 - Ferritin - folate - Iron - VitD are low in their ranges - they need to be OPTIMAL....


I know that lack of B12 is my problem because when the GP let me have a single injection to try, I felt great for a couple of weeks. But he then said that as the effect was only temporary, it must be placebo (I haven't shot him yet lol) and refused to discuss the issue any further.

My latest test results showed my level as 504 ng/L in a range of 120-525 so he says that is fine. But that's the level of B12 in the blood, and not the level of B12 in the cells. Last May I asked to be referred to a specialist for proper investigation into my B12 status but am still awaiting a reply from the hospital despite two more emails to the specialist.

If your car won't run properly, and the mechanic has ruled out that it is a problem with the electrics, then it has to be a fuel problem, ie lack of it going into the engine. If the mechanic measures the amount of fuel in the tank, and says that's fine, it doesn't mean that the fuel is getting through to the engine. In fact, if there is a blockage in the fuel line, then the level of fuel in the tank will remain high. So a high level of serum B12 does not mean that you don't have a problem with B12 deficiency. I've tried to explain this to my GP who looked completely baffled - you may have more luck with yours if he/she wasn't one of those the other medical students must have practised their lobotomies on !


Borrow from if they have one available or buy from Amazon Martyn Hooper's book 'Pernicious Anaemia The Forgotton Disease.

Pernicious Anaemia is not always diagnosed but many have a B12 deficiency and he says that we are all extremely low in this essential vitamin. He said we should aim to have a blood level of around 1,000 to 2,000. He says that we can lose cerebral fluid and I have also read that B12 deficiency can also cause alzeimers etc.

He also says that if we have an injection, after 24 hours most of it has been excreted in our urine and some do need injections more frequently. We can also use sublingual methylcobalamin as they are good as the bypass the stomach.


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