Hi, I read somewhere low levels of iron prevents free t3 from getting into cells and leads to low free t4 and high free t3 and may make hypothyroidism symptoms worse, here's the link:
stopthethyroidmadness.com/p...
Can iron deficiency really affect hypothyroidism or it's just an idea?
There's a lot of confused thinking in this area. When I have time I will collate the research and post on the forum.
1. Anaemia is common in hypothyroidism, the two go together.
2. Severe anaemia can reduce fT4 levels and elevate TSH a little.
3. There are claims that anaemia inhibits T4 to T3 conversion, the only evidence for this I have found is an obscure experiment in rats. Other studies don't find a link. The pituitary relies on deiodinase to respond to fT4 levels, if anaemia affected deiodinase then the pituitary would not respond to fT4 and TSH would go high.
4. 'getting into cells' is a bit of a nutty concept. If the hormone didn't get into cells then the pituitary could not respond to fT3, fT4 and TSH would be at astonomical levels. It's not acceptable to quote vague references (which they probably haven't read) and then propose vague implications. I've never seen anything to suggest typical levels of iron deficiency inhibits thyroid hormone entry into cells (which is an active process).
Your reference to low fT4, high fT3 contradicts the most common assertion that anaemia stops conversion of T4 to T3.
Anaemia is common in hypothyroidism and tends to be difficult to treat until the patient's hypothyroidism is sorted. It makes sense to supplement with iron whilst treating the hypothyroidism. Anaemia can reduce thyroid hormone levels a touch but this is irrelevant if you are taking hormone tablets.
One quarter of the world's population is anaemic, they are not all hypothyroid. Keep it simple, use common sense, avoid vague references like 'getting into cells' that are not backed up by evidence.
I thought the pituitary reacted to thyroid hormone levels in the blood, not the cells.
Yes, but the circulating hormone has to get into the pituitary cells so it can respond. So, unless someone can explain how low iron stops hormone getting into peripheral cells but magically lets it get into pituitary cells the "can't get into cells" idea is a non-starter.
Thanks for replying...but I'm still confused...so what is cellular or tissue hypothyroidism?
Cellular or tissue hypothyroidism is misleading terminology but the concept is fine. What I believe people who use these terms mean is that the pituitary responds normally to hormone but there is imparied hormone function in peripheral tissues. This is valid and I'm sure it happens, I refer to it as peripheral resistance to thyroid hormone (peripheral RTH). This should not be confused with the genetic forms of RTH.
There are various mechanisms by which this can happen. The pituitary has different thyroid hormone receptor types and can bind hormone in different ways. Also, peripheral type-2 deiodinase (T4 to T3 conversion) is regulated by various mechanisms including "ubiquination". These differences between how the pituitary and other tissues use thyroid hormone open up opportunities for peripheral RTH, especially by endocrine disrupting chemicals (EDCs). Also, a disrupted hypothalamic pituitary thyroid axis will affect peripheral deiodinase and thyroid secretion. As you can see this gets very deep and complex, I'd rather not go into more detail. Suffice to say you can have peripheral hypothyroidism with normal pituitary function and normal blood test results.
Thank you very much for replying...
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
onlinelibrary.wiley.com/doi...
Hence the ever repeated question on here to people......have you had vitamin D, folate, ferritin and B12 tested. They very often need to be at optimal levels, not just in range.
Each of these can cause their own problems. Beware however that this paper assumes that if blood tests are 'normal' then symptoms can't be due to hypothyroidism. This is contrary to patient experience. Certainly correct any deficiencies but don't ignore signs and symptoms that are due to hypothyroidism.
Thanks for sharing the article...yeah, I had a blood test two weeks ago but haven't visited my doctor yet...everything seems to be fine but ferritin was very low...I thought my problems may be caused by iron deficiency...
Here's the results:
FBS 91 reference range (74-100)
BUN 15 (7-20)
Creatinine 1 (0.7-1.4)
Triglycride 68 Normal (150)
Cholestrol 146 Desireable <200
Calcium 9.1 (8.5-10.5)
Phosphorous 3 (2.5-5)
Ferritin 10 (10-100)
Vitamin D3 60 (32-78)
TSH 0.8 (0.4-4.2)
Free t3 4.2 (1.9-4.3)
Free t4 1.2(9.0-23)
Yes your ferritin is very low
Eating liver once a week should help
But GP should run full iron panel to test for Anaemia
humanbean and SeasideSusie may comment
No B12 or folate tests?
These are often low if ferritin is low
Not sure about vitamin D, are you in UK?
Normally vitamin D is better nearer 100nmol, assuming you are UK based
I live in Iran, unfortunately most doctors here don't check B12 and folate...
Your Ferritin is dire. Low Ferritin may suggest iron deficiency anaemia so you need an iron panel and full blood count. Ferritin needs to be at least 70 for thyroid hormone to work, yours is low enough to need an iron infusion.
If your Vit D is 60ng/ml then it's perfect as the Vit D Council recommends 40-60ng. If it's 60nmol/L then it's too low as the recommended level is 100-150nmol.
Thanks for replying...
My ferritin and Vitamin D are always low but my doctor priscribed 50000 iu vitamin D3 capsules even before doing blood test and told me to do it a week after taking the caps...but I haven't noticed any improvement yet...don't know what he will do for iron deficiency...
Can you say how often you are supposed to take 50,000iu D3? To prescribe such an amount before doing a blood test is ridiculous. If your level is 60nmol/L then it is lower than recommended but not low enough for a doctor to prescribe anything let alone 50,000iu D3. At that level most doctors would tell the patient to buy their own. No point in testing a week after taking the D3, it needs to time to work.
D3 has important cofactors that are needed but your doctor won't tell you about those because they're not taught nutrition. You also need to take magnesium and Vit K2-mk7. Magnesium helps your body to use the D3.
D3 aids absorption of calcium from food and K2-mk7 directs the calcium to bones and teeth where it is needed and away from arteries and soft tissue where it can be deposited and cause problems.
You need to ask your GP what he I tends to do about your Ferritin, ask for an iron infusion. And if not already done you should ask for a full blood count and iron panel.
They gave 30 caps which I have taken 21 of them...I also had a syrup called calcicare which contains calcium, zinc, magnesium and vitamin d3...vitamin D3 level seems to be optimal now as lab unit is ng/ml...Is taking rest of them dangerous?
Can't wait to start anemia treatment and see its results...It's my last hope to feel like myself again...
With your level now 60ng/ml you are now at the recommended level and need to maintain it. You have to find your maintenance dose by trial and error and that may be 2000iu daily, maybe more or less. We need to test twice a year to make sure we keep our level with the recommended range.
Was your calcium tested and found to be deficient? We shouldn't take calcium unless we know we need it so testing is essential before supplementing.
He prescribed calcium syrup before the test but it was only 250 ml, I'm not on any calcium supplement now...
My vitamin D3 has never been more than 33 ng/ml, even in the summer or after injecting but this time it's very higher than usual...
Iron deficiency symptoms..? GP says not.. advice please ! 
Query re iron deficiency blood tests when hypothyroid and low B12
Hypothyroid - How to best supplement with iron
Does hypothyroidism affect your immune system
Does hypothyroidism affect urinary tract and bladder? 
