FT3 levels dropping over time - what to do?

[Bearo]

When I started on Levo about four years ago I seemed to be a good converter. I’ve had some fluctuations in dosage and every time I’ve rechecked FT3 it’s gone down. It never goes up. I now seem to be a poor converter.

2021 on 100mcg Levo - weight loss on this dose and frequent number twos

TSH 0.01

FT4 24.9 = 129%

FT3. 6.5 = 91.89%

2022 on 85mcg (my reduction)

TSH. 0.02

FT4. 18.2 = 62%

FT3. 5.1 = 54%

2023 on 75mcg (GP reduction) increased depression and painful slipping jaw, shoulder pain

TSH. 0.02

FT4. 18 = 60%

FT3. Not measured

2024 on 89mcg (my increase)

TSH. 0.01

FT4. 24.4 = 124%

FT3. 4.8 = 46%

2024 - on 85mcg (my decrease)

TSH. 0.01

FT4. 20.4 = 84%

FT3 4.8 = 46%

2024 - Oct - on 85mcg

TSH 0.02

FT4 19 = 72%

FT3 not tested

2024 - Nov - on 75mcg (GP decrease)slight increase in lethargy/depression, plus tendon type issues

TSH 0.04

FT4 18.2 = 62%

FT3 4.1 = 27%

The ranges were FT4 12-22 or one is 11-22. FT3 range is 3.1-6.8.

So anything above 89mcg is too much for me and 75mcg is not enough. I’m back on 85mcg

My vit d is around 100, B12 is a little under the 500 mark,so could be higher, folate and ferritin are ok, iron bumps along the bottom of the Full bloods cut off point. I’m 71 and have never been on HRT.

My HbA1c is 43 putting me in prediabetes range. I’ve been trying to improve diet but only recently trying to avoid too many carbs…..not enough to affect conversion, I wouldn’t have thought.

is it time to try to source some Lio or are there things I should do to improve conversion?

Or, as no obvious symptoms when I’m on 85mcg Levo do I just plod on?

[Regenallotment Ambassador]

Hi Bearo,

I looks to me like 85mcg and allowing 12 weeks to settle is likely your sweet spot. Judging by those blood tests these changes are quite frequent.

Your iron could be impacting, it has a direct correlation to the effectiveness of my thyroid hormones replacement, I have to adjust my heme iron supplement up and down in the same way I adjust Levo/Lio to be optimal.

“Bumping along the bottom”, not a good sign. Do you have a recent full iron panel including ferritin result to share?

[Bearo in reply to Regenallotment]

Thanks for your reply Regen, I’ve never had a full iron panel and now that I’m over 70 I’ve discovered I no longer get the annual full blood test, cholesterol, etc. My last ferritin was 70 but Haemoglobin was generally one number above the bottom of the range.Red cell distribution width was poor, too. Whenever I mentioned this I was told it was ok, even ‘that’s good for a woman’.

I don’t eat red meat but could add a bit to my diet. I was eating some liver once a week but haven’t kept that up. Will restart.

Are iron supplements recommended for someone who is not technically deficient but only just in range?

I’m considering reducing carbs to lower my blood glucose but I realise this may affect conversion too. (I love carbs so would find this hard, anyway)

[Mednews4 in reply to Bearo]

I noticed you mention limiting carbs. Is limiting carbs preventing T4 to T3. With hash I’d, I don’t convert well and take lio but I don’t eat many processed carbs or much grains. This is the first I have read this.. Hope you feel better soon. I also still can’t seem to get my ranges of t4 and t3 to be optimal - up 2/3 of the range.

[Bearo in reply to Mednews4]

Yes, carb restriction is known to reduce conversion, but I don’t know how restrictive your diet would need to be to have an effect. If you are on Lio I’d assume you wouldn’t have a problem but obviously I’m wrong to think that.

[Regenallotment Ambassador in reply to Bearo]

Yes you would definitely benefit from increasing dietary iron intake then 👍

I wouldn’t supplement unless you had a recent iron panel blood test result.

Yep a healthy balanced diet aids conversion for hypos. But so does optimal vits 👍