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Thyroid UK
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Good morning

I have just got my latest results and my TSH has gone even lower <0.005 and I am seeing my GP next week and I am sure he will say I have to lower my NDT. However my FT4/3 have lowered and some of my symptoms are back. My ferritin levels have increased back up but the only change I have made is going gluten free for the last 4 months which shows in the antibodies tests - at least one thing going in right direction.

How low can the TSH go before I should be worried? As I am mainly concentrating on FT3/4 and symptoms to manage me. I give below results for any help.

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The TSH is totally irrelevant when you're on thyroid hormone replacement, unless it goes high. Doesn't matter how low it goes, especially not when you're taking T3. The important number is the FT3. Unfortunately, doctors don't understand that.


Thanks that is very clear to tell dr and reassures me.

My last test 3 months ago had my FT3 at 6.7 (3.5-6.5) just over but I wasn't experiencing any symptoms of over active and FT4 was only 17.3 (9-24). How do you get them both to top end of range - is that the part where vitamins come into effect?

I was better when FT3 was high end and not 5.08 (3.1-6.8) - so I am thinking I need to increase slightly. I am currently on 3.1/2grains - was thinking 3.3/4 for 6 months and then blood test?


Yes, you could try that.

You don't need your FT4 at the top of the range, because there is T3 in NDT. Therefore the body only hangs on to the T4 it needs, and it doesn't need as much. This is where so many endos make a mess of things, trying to increase the T4 on NDT.

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What supplements do you take?

Your vitamin D could be a bit higher

Ferritin can be high due to Hashimoto's.


My Vit D was only 30 in Feb & I took 10,000 dose, by June it went up to 98 (75-200) so reduced dose to 5,000. But now it has gone down again. Should I up the dose again?

I take Vit C with (I have just noticed!) Magnesium Ascorbate with Bilberry & Grapeseed Extract. 1000

Vit B12 - that has increased from 351 in Feb to 594 now so will keep on with that as it say consider reducing dose when > 725

Vit Bcomplex

All the above taken after breakfast.

At night I take a probiotic and Magnesium 150mg

First time I have tested Magnesium and it says it's high 1.01 (0.6-1.0) - should I stop taking this?

Very strange about the ferritin going up.


All these sound good.

Vitamin D definitely going in the right direction

Magnesium you could reduce dose, but personally I wouldn't stop it, it's needed to help vitamin D.


Did you stop vitamin B complex 3-4 days before testing? If not better to do so in future



humanbean is iron and ferritin expert. Might have an idea about ferritin ?


No I didn't stop Vit b complex before testing I will next time.

Thank you so much for your help.


Your zinc is on low side

Might want to add that to supplement list

Either different vitamin C with zinc

Or add zinc on own, eg Solgar zinc piccolante, perhaps 3 x week


Thanks will try that


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