Vitamin D, B12, Folate, Iron — Why are these so... - Thyroid UK

Thyroid UK

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Vitamin D, B12, Folate, Iron — Why are these so important?


I've noticed that contributors on this forum often recommend supplementing these vitamins, and I was wondering why?

Are there any studies that suggest these particular vitamins are required for thyroid hormone use, or are otherwise beneficial for hypothyroidism? I realize that hypothyroidism can cause digestive issues that can in turn lead to deficiency in many nutrients, but I'm looking for more information on why these specific vitamins are beneficial for hypothyroidism in particular.

Thank you!

15 Replies

Not quite - we suggest testing them and if found to be low or deficient then supplement.

Thyroid UK's article about the role of vitamins and minerals in thyroid disease

It just makes sense to test all-i was hyper and have hashis and graves and celiac and found out that i had a very dire ferritin level of 10 and folate low, i now have been supplementing with iron supps and feel so much better-iron def is a killer i was very exhausted, very breathless, heart palps etc, if it wasnt for the great people on this forum telling me this my useless gp or endo would not have even mentioned it-i think different now, everything should be tested when we feel unwell. 😊

I totally agree. I wish I understood why doctors don’t.

Glad to hear you’re feeling better with the supplements. Liquid iron has definitely helped me out with energy and breathing issues, although my ferritin was never as low as 10! Again, so glad you got that sorted.

Did you find that supplementing folate made a noticeable difference as well?

Yes i have only started on folate recentley as i tried to raise this with more foods containing folate but it was not doing a thing-ive been on them for around 1 month and have noticed a little difference-i have just been for a repeat iron tests today to see if any improvement-i really do hope so-im sure it has because im better than i was back i january.😊

Gps dont tell you anything-i am a great believer if you want anything doing do it yourself.xx


Here you go .....official in black and white

Written by leading UK endocrinologists

See Box 1. Towards end of article

Some possible causes of persistent symptoms in euthyroid patients on L-T4

You will see low vitamin D, folate, ferritin and B12 listed

Thank you! I want to get these values tested so I know whether/how much to supplement, but I feel like I need to have some evidence of efficacy before I request the tests. This is perfect.

As someone who takes T4/3 therapy, I found this "Wiley" Q & A document rather depressing. How do others feel about it?

SlowDragonAdministrator in reply to Hennerton

It’s the only official document I know of to mention vitamin deficiencies

Otherwise.....I wouldn’t post it

Hopefully will be superseded by new NICE guidelines next year with more positive outlook on T4/T3 options

The inconclusive studies on combo therapy can be pretty discouraging... and the more I read, the more it seems like modern medicine doesn’t understand the thyroid well enough to truly replicate its effects with any kind of drug therapy.

But I take T3/T4 as well, and I know I feel better with T3 on board.

SlowDragonAdministrator in reply to ilyfunnybunny

I didn't really function at all, barely able to walk at all (10 mins slow shuffle) on just T4.

Addition of small dose of T3 been transformative, after improving low vitamins with supplements and strictly gluten free diet first. DIO2 gene variation too

Thanks for your comments. What I cannot understand is that people like us exist, who feel so much better on T3, so why can the studies never find anyone and we are told that all their trials are inconclusive?

I am at a total loss to understand the demonising of T3, when all around us patients are taking drugs with horrendous side effects and this is considered fine and dandy. It is all a mystery...

mea, actually the condition is very complex because of all the organs involved. First the stomach becomes inflamed and from there it is difficult for it to breakdown nutrients particular B12 and amino acids. Unless the gut issue is repaired things go downhill. Many times that gut issue is gluten or dairy which may also cause leaky gut and the immune response gets quite activated. It's a good idea to heal the problem or at least to replace the nutrients that your body cannot derive from food. Minerals are a big problem.

SlowDragonAdministrator in reply to Heloise

Pity that most endocrinologists are completely disinterested in any of this.

The gut is not remotely in their area of interest

Heloise in reply to SlowDragon

It is a shame because putting the onus on the patient to work out their treatment is very unfair. But everyone needs to manage their health and learn to make good choices.

We've had valuable information from great functional doctors who may be available personally. I feel very good about my own health and think many of us can actually achieve some success on our own. And with people like you who offer suggestions it makes it that much easier. Best wishes, SlowDragon.

Folate (not folic acid) is a really important one for pretty much everything, not just hypo. Look up methylation. Low b12 damages nerves and can cause hypo- and dementia-like symptoms. Possibly should add riboflavin to the list as b2 is needed for many body processes too.

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