Thyroid UK

Why do we need to get our ferritin and vit d levels checked when hypothyroid?

I have chronically low ferritin and vitamin d levels, (ferritin under 5 for 18 months and vitamin d under 40)

My endo said that my vit d was fine and that my ferritin can only be due to heavy periods which I don't think I have. Is he correct? Or is it something to do with being under active? I take 150mg levothyroxine a day, reduced from 175 6 months ago.

Many thanks


9 Replies

I'm sorry I cannot answer re ferritin and Vitamin D and other members will respond but did you feel unwell on 175 levothyroxine that he reduced it to 150mcg.


I have felt really unwell for 2 years now due to adrenal insufficiency. The reason it was reduced was because my tsh was 0.03 and the gp felt that I was over medicated and it may be making my adrenals work harder. That was 6 months ago and my tsh is still 0.03

I also have lupus so symptoms get mixed up. My endo who was looking after my adrenals is now going to investigate my thyroid....


I am sorry you are still feeling unwell. They have no reason to adjust your medication due to the TSH result alone as it can cause problems. This is an excerpt and cursor down to the date January 25, 2002 to read the answer. Extract:

Dr Lowe: Your observations don’t suggest to me that your pituitary gland isn’t functioning properly. In fact, your observations are consistent with what science tells us about a patient's T4 dose, her TSH level, and her metabolic health or lack of it. If the goal of a doctor is metabolic health for his patient, he has no scientific basis for adjusting her thyroid hormone dose by her TSH level. If the doctor is going to make the imprudent choice of treating the patient with T4 (rather than T3 or a T3/T4 combination), he should be aware of the relevant physiology and treat her on the basis of it. Otherwise, he's likely to ruin her health, as your doctor appears to be doing to yours.

The TSH level is not well synchronized with the tissue metabolic rate. (Probably most doctors falsely assume that studies have shown that the TSH and metabolic rate are synchronized. But despite my diligently searching for years for such studies, I’ve yet to find them.)


This is a link re ferritin and Vitamin D. You will see how important both are for the thyroid gland and health in general. Your GP should give you supplements of Vit D and members will respond to this and ferritin as some have used supplements to increase both.

1 like

Thank you so much.... Your information is really useful. Funnily enough I have the opposite to what I would have expected with SLE according to the article but have wondered for some time if I suffer with malabsorption issues. My endo has suggested an iron infusion to give me a much needed boost. I am 47 going on 80 and I am at the point where all my friends ask me how I am every time they see me.... Never wanted to be defined by my illness but I think I am now


We really are unaware of how much vitamins/minerals are needed when we are well. With hypothyroidism we seem to be depleted and this is a link and you will see that the last 3 are particularly important.

You are young and hopefully if your Endo is good you will soon feel much better. It is quite usual if we have one autoimmune condition that we will have others.


Earlier this year I found I was severely deficient in Vit D. The symptoms are very similar to hypothyroidism. And , gues what, I was told it was my age!

But the endo found it and several months later I feel much better.

There is no nation standard test for Vit D. Every lab uses its own test, and will provide their normal, and a small range on each side . If you fall in this range you will be told you are normal. Reach normal, stay there for a few months, see how you feel then either go up or down accordingly. It takes about 3 months to notice the's slow.

Do not take Vit D without a is easy to,overdose which is really not wise!

Hope this is useful



The Mayo Clinic site states that taking 50,000 IU of Vitamin D3 daily for months and months is potentially toxic. Do you think there's any chance she may do this?

Here's the WebMD site for Vitamin D3 recommendations and warnings:


Being hypo is very often connected with low stomach acid. Because of that iron is not being absorbed very well. In order to increase absorbtion drs usually advise taking vit C (at least 500 mg) together with iron.

I've had stomach problems for years (am planning to test for H. pylori). And my ferritin dropped to 27. Do you tend to get heart-burn? As I understood from what my dr told me, it is one of the most common symptoms of low acidity. Although I dont have it.


You may also like...