Thyroid UK
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Advise on blood test pls...ft4&ft3 still too low


I am very disappointed with my thyroid result this time.I increased my levo from 50mcg/day to 50mcg and 100mcg alternate days but it only reduced my TSH and showed no effect on my my ft4 and ft3 levels. Instead,they got even lower.


TSH 0.13 ulU/ml (euthyroid 0.25-5/Hyperthyroid <0.15 :Hypothyroid >7.0)

FT4 15.78 Pmol/L (9-25)

(on 24/3/2016 it was 17.52)

FT3 4.58 Pmol/L (4-8.3)

(on 24/3/2016 it was 5)

Ferritin 26.7 ng/ml (6.24-137)

Vitamin D 39.8 ng/ml (deficeint:<20ng/ml ,insufficient 20-29 ,sufficient 30-100 ,potential toxicity>100)

Cortisol-Total (PM) 7.9 ug/dL (2.9-17.3)

Vitamin B12 1301.0 pmol/l

I was taking vitamin D and Iron supplements when I had my previous tests done (and also zinc and selenium sometimes) maybe this could have showed some improvement in my last tests.

I know that my vitamin D and ferritin and quite low and I will start supplementing again.

But I want to know how would I know if I need Copper along with Iron supp.?

I am also afraid of iron and vitamin D toxicity .So what should be the safe dose that I can take for 2-3 months before I get tested again for my thyroid.

Wouldl Dessicated Liver supplement be a better choice than a plain Iron supplement?

Or can I take an Iron supplement containing Copper,Vitamin b12,folate and vitamin C ?

My Vitamin B12 is high according to the test above so my doctor asked me to stop the suppelments.I was taking 5000mcg sublingual methylcobal.I don't want my levels to fall so how much should I take to maintain this level?

I am also thinking about trying Thyro Gold instead of levothyroxin and an Adrenal Cortex glandular supplement.Should I raise my vitamin d and ferritin first and see if my hypo symptoms resolve or should I stop wasting time on levo?

I can't seem to keep my vit d and iron high.They fall easily if I stop supplementing.

My major symptoms are eye allergies,fatigue,un-refreshed sleep,finding it hard to get out of bed in the morning and feeling sleeping even if I had slept for 8-9 hours,depression,anxiety,acne,pre-orbital dark circles around eyes,cough with mucus in the morning,sugar cravings,breast tenderness,low back pain and PMS.

7 Replies

Last I looked, the actual iron content of desiccated liver supplements was pretty low.

I suggest that ferritin and/or haem (heme) supplements might be better as sources of iron.

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Have you ever had your thyroid antibodies tested? Ideally need both TPO and TG antibodies tested. If one, or both are high this means hypothyroid is caused by autoimmune issue and is Hashimoto's (by far the most common cause)

If GP has never tested for antibodies, ask him politely if he would. If not can get done privately via Thyroid Uk

Many of us with Hashimoto's find adopting a 100% gluten free diet reduces symptoms, calms over sensitive immune response and can even slowly lower antibodies over time.

Good idea to get coeliac test BEFORE going gluten free. But even if this is negative, going gluten free can give great improvement.

Vitamin D

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Thanks for your reply.

I had my TPO tested twice and it was under the limit so doctor didn't bother to check my TG antibodies and said that I don't need anymore testing for antibodies.

I don't have hashi symptoms but I have always have had gut issues.I blame it on my not so good diet.I am a skinny person and I can't go on any restricted diet because I would get under weight.I do however avoid sodas,candies,cookies,chocolates and have reduced junk food to 50%.

I try to eat healthy as much as I can.



Your thyroid levels aren't low, but both could be higher. Your symptoms, other than fatigue, aren't typical hypothyroid symptoms, and the fatigue could be due to low ferritin and vitamin D.

I would supplement to improve ferritin and vitD before making too many other changes. Good levels of ferritin aid absorption of Levothyroxine and good vitD levels aid T4 to T3 conversion.

Ferritin is optimal halfway through range. Supplement 2 or 3 x 210mg Ferrous Fumarate and take each tablet with 500-1,000mg vitamin C to aid absorption and minimise constipation.

This link will guide you how much vitamin D to supplement

Iron and vitD should be taken 4 hours away from thyroid meds and you should retest 4-6 months after supplementing.

B12 is high because you are supplementing 5,000mcg. You can maintain levels by reducing to 1,000mcg. It's a good idea to take a B Complex vitamin too.


I am not a medical professional and this information is not intended to be a substitute for medical guidance from your own doctor. Please check with your personal physician before applying any of these suggestions.

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Thanks for your reply Clutter xx

I agree that low vit.D and ferritin could be causing fatigue but even when my levels were 50% of the range,I was still tired all day long.

Anyway,can vitamin D and iron be taken together?

I have vitamin D3 drops and chewable 100mg iron tabs.Can I chew these tablets soon after I have taken D3 drops?

I am also taking magnesium citrate (effervescent ) since 3 days now because I read that vitamin D should be take together with Mg and people with Vit D deficiency are actually deficient in Mg.

So I am wondering if I can take all the supplements together along with my high potency multivitamin+mineral tablet i.e Zn,Iron,Vit.D3 and Mg.

Can you please also tell me what should be an optimal level for VIt D3 and ferritin? I read online about some doctors who say that the optimal level should be 60-70 and some 50 and some say that it shouldn't be more than 80.



Check whether your iron should be taken with or away from food. The vitC should be taken with iron. If the iron can be taken with food I think it will be okay to take it with D3.

D3 is best taken with the fattiest meal of the day as fat helps absorption.

Magnesium is usually taken at bedtime as it promotes rest.

Ferritin is optimal half way through range so > 68.0. VitD is optimal around 40ng/ml.


Thanks again for replying But if Vit D is optimal around 40 then this means that I already have sufficient levels because mine is 39.8ng/ml.


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