I've seen replies/comments on a few posts recently (but can never find them again) stating things along the lines of "low vitamin levels can cause TSH results to be lower". I'd like to learn more about this and understand the relationship but can't seem to find anything myself. Does anyone have any useful links for me or is able to explain? I understand good vitamin levels are critical for good thyroid function, so my assumption would be that poor vitamin levels would contribute to poor thyroid function and therefore TSH would be higher while vitamins are suboptimal.
Thank you for any help/knowledge sharing you can give!
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Myalikki
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I tend to agree with you. It is often asserted that 'good vitamin levels are needed for thyroid function' but I've not seen any good evidence. I'm sure it's possible that certain severe deficiencies could cause a reduction in secretion or impaired deiodinase but these actions would lead to an increase in TSH. Such an action, if it occurs, would tend to be misinterpreted as primary hypothyroidism which might not be adequately treated.
Hypothyroidism can certainly lead to deficiencis such as poor iron status. We then get to a chicken and egg conumdrum where improvement in thyroid status and nutrients improve together. The evidence I've seen suggests it is hypothyroidism causing deficiencies rather than the other way around.
I can never remember what the impact is supposed to be of good nutrient levels on TSH, but my conversion of T4 to T3 seemed to improve after my vitamin and mineral levels improved.
But the main reason I take vitamins and minerals is because they make me feel better - and that is my aim with everything I take, prescribed or otherwise. Before I started taking nutrients some of my levels were poor, or even under range in the case of iron, although I didn't actually test that many of them.
I also, after taking thyroid hormones and using good quality supplements rather than multivitamins, actually fixed some health problems that I'd had for decades. E.g. I'd spent my entire life from before I went to school with issues with my feet (plantar fasciitis). That problem went away. I had some other chronic health problems too, and some of them have disappeared entirely or have improved a huge amount. I credit having very high levels of B12 for some of those improvements. If I stop or cut back on the B12 those problems start coming back.
But as jimh111 says, hypothyroidism leads to deficiencies. If we all start taking Levo or other thyroid hormones at the same time that we start taking nutrients then we might not be certain which of them is helping.
Thank you humanbean and jimh111 , lots of things to be thinking about. I absolutely agree that the whole point of taking anything is to feel better, and as I am largely at the start of hypothroidism journey, I too am facing the conundrum of being able to work out which change led to what improvements.
My reason for asking about vitamins and the relationship with TSH is because I am currently taking 75mcg levo and suspect I need about 90mcg based on body weight, so I will need a further dose increase. While my GP was not resistant at my last review, he didn't offer a dose increase when my TSH was about 4.5 (slightly over range), he did in fact say "I'm happy with your test results", but as soon as I said "I'm still only taking 50mcg levo and I am still very symptomatic", he told me to go up to 75mcg. Based on this experience I am wondering if my next review will involve more resistance, and so I am thinking it would be best if my TSH is helped to be as high as possible. I know my vitamin levels haven't been amazing so far (recently completed a loading dose of Vitamin D, my active B12 is borderline, and my folate is pretty much on the floor, only my ferritin seems okay, and I suspect that is largely a reflection of inflammation!), so was wondering if fixing them all in one go (rather than one thing at a time) between now and next review is likely to help or hurt me getting a dose increase... I don't think there is a straightforward answer, but would still be interested to read any relevant research or links.
Thank you both for your time and sharing your thoughts!
Vitamins are vital for optimised health but I think it more the nutrients such as iodine or selenium deficiency as both are heavily implicated in the role of the making and utilising of thyroid hormone.
Iodine should never be supplemented without testing first but deficiencies are now being seen in pockets of the UK. Selenium it seems can be safety supplemented at 100mcg a day as per numerous practitioners advice including that of Thyroid UK’s Melissa Cohen.
Vitamin deficiencies caused by years of low thyroid hormone should be addressed individually but once levels become optimised, a multivitamin tablet is often enough to maintain levels.
Thank you very much for this, have just given it a read through.
For anyone who would like info regarding TSH without reading it: This review found that most studies that tested Vitamin D levels and TSH found that TSH came down as Vitamin D levels went up. This was found in hypothyroid patients and in euthyroid, healthy adults.
More generally, the review presents significant evidence that a correlation between Vitamin D and thyroid function does exist, and that Vitamin D is strongly associated with hypothyroidism and several relevant markers, although there are still some studies that found no significant association at all. Even if the association is accepted, it remains unclear whether this is a causal relationship in either direction (i.e does being hypo make it harder to absorb Vitamin D? Or does being deficient in Vitamin D make one more likely to develop hypothroidism?) or the mechanisms through which this might be taking place.
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