Thyroid UK
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Normal TSH, lowish FT3, highish FT4?

Am on 50-75mcg/day levo.

What do these results suggest please? Do they perhaps suggest poor conversion T4 to T3? And if so would that suggest adding in some T3? Or have I got the wrong end of the stick?

TSH 0.8 (0.4 - 4.5) (In September my TSH was 0.4, no other results)

FT3 3.2 (4 - 8.3)

FT4 22.3 (10 - 24)

[I wasn't given the reference ranges, I've assumed those in brackets.]


2 Replies

Hi Copper, I think you are absolutely correct. The question is "why". I've been posting videos explaining problems even though taking hormones. You may have too high testosterone levels believe it or not. You may not have co factors to help convert. You may have adrenal issues. You could have antibodies attacking your T3. I will say that when I switched to T3 only, I still could not increase my dose which was the problem I had with natural thyroid. But I did do better on NDT than on thyroxine.

I'll post the videos that may pertain to you....but there are 22 in total. Only five minutes each.


To help (or more to the point to allow) your body to convert the T4 you are taking into the T3 it desperately needs you have to have certain vitamins, not just in NHS range, but at optimal levels for thyroid sufferers.

Have you ever had your vitD, Ferritin, Iron, B12 or folates checked and if so what were the results? Your ferritin level (iron storage) needs to be near the 70 mark for you body to be able, not only to convert T4 to T3, but to then transport the T3 into your cells which is where you desperately need it.

Unfortunately you may struggle on T3 as well if your vitamin levels aren't right.

Have a look at this link that will explain some of this.

Moggie x


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