Hi!
If we take T4 to the point our TSH is near 1, doesn't that make our Thyroids "shut down", and therefore, the remaining T3 produced by the gland will no longer be there? I'm asking this because curiously, the more T4 I take, the LESS T3 I produce!!
Well, that shouldn't happen with a TSH of 1, but lower, yes, that's exactly what happens.
However, even with a TSH much lower, it is possible for some people to convert enough T4 to T3 to keep them well. And, if you only take enough levo to keep your TSH above 1, you won't have enough T4 to convert to T3. Remember, your thyroid is sick, for whatever reason, and that's why you need thyroid hormone replacement in the first place. So, it won't be making that much T3, anyway. So, you're sort of stuck between a rock and a hard place, and have to make the best you can of it.
Unfortunately, doctors just don't understand any of that. If they did, they would understand the importance of rescribing T3 to those that don't convert well - for whatever reason. But, the truth is, most doctors don't even know what T3 is! Or what it does.
the more T4 I take, the LESS T3 I produce!!
Yes….that happens for thousands of thyroid patients …..pity many medics can’t understand this conundrum
How much levothyroxine are you currently taking
Are all four vitamins optimal, this might help improve conversion of Ft4 to Ft3
Hi Slow Dragon, I'm currently taking 75 mcg a day, TSH is 1,27 but if you analize the complete series (2017-2021) it seems I was producing more T3 WITHOUT meds (although I was subclinical) and when I intruduced Levo my T3 started dropping even more. Does that mean I am better off WITHOUT levo?As for vitamins, the only value which is off is ferritin (14). I'm taking Iron supplements for that. I over supplemented with B12 and it went from 250 to 930 so I stopped there.
75mcg is only one step up from starter dose levothyroxine
Unless very petite it’s unlikely high enough dose
Approx how much do you weigh in kilo
What were most recent Ft4 and Ft3
ALWAYS test thyroid levels as early as possible in morning before eating or drinking anything other than water and last dose levothyroxine 24 hours before test
Do you always get same brand levothyroxine at each prescription
Clearly ferritin levels terrible
Are you vegetarian or vegan
Low ferritin is interlinked with thyroid hormones
healthunlocked.com/thyroidu...
It takes many months to improve low ferritin
Once all four vitamins are optimal retest thyroid levels
Optimal vitamin levels are
Vitamin D at least around 80nmol and around 100nmol maybe better
Serum B12 at least over 500
Active B12 at least over 70
Folate and Ferritin at least half way through range
What vitamin supplements are you currently taking
You're right that in some people, increasing Levo by more than a certain amount actually gives them less T3... This excellent article explains how that happens:
thyroidpatients.ca/2018/12/...
"Ubiquitination: The glass ceiling of T4 monotherapy
BY THYROIDPATIENTSCA on DECEMBER 30, 2018 • ( 19 )
UBIQUITINATION: This is the “Glass ceiling” of T4 monotherapy — in some patients, there is a biological limit on how much T3 they can get out of treatment with T4 thyroid hormone alone (Synthroid, levothyroxine)....."
But i'm sure TSH of 1 is not low enough to cause the thyroid to completely shut down.. the regulation of production /conversion of T4 /T3 from the thyroid will obviously now be a bit different from someone who isn't taking exogenous thyroid hormone .
Remember, most perfectly health people have a TSH of near 1 and may of them have a TSH level slightly below 1 , so there is nothing about a TSH of 1 that means thyroid's stop producing T3.
Thank you for posting this article tattybogle I have never heard about T4 limiting T3 conversion!
Thanks!!
I have also read that the clinical relevance of long-term lower serum T3 (compared to healthy individuals) is not well known. They don't know if it has clinical importance.I just don't know what to think anymore. Are we at risk if we don't take T3 as well? The treatment with T3 is highly impractical (you need many doses a day, everyday) and the long term outcomes are not fully understood.
I'm pretty sure there is plenty of stuff on here showing 'lower T3 is a clinically relevant', and carries increased risks ? ... but i can't remember any references off hand. Others will know if you write a new post asking that Question.
T3 treatment isn't any more impractical than Levo for quite a few people on here who take it all in one daily dose ...
and as for those who don't function well on Levo, and need to take a few T3 doses through the day .. i guess they'd argue that 'not being well enough to work is also pretty impractical' And some of them say they don't need to keep T3 dose as far away from food as they do for levo .
Long term outcomes of adding T3 not understood ? ... the same could be said for treating with just T4 .. that's never been tested properly either... they just replaced NDT with Levothyroxine sometime around the1950's ...
what are the long term consequences of running the system with relatively higher T4 / relatively lower TSH / relatively lower T3 .. which is what usually happens on Levo ?
T4 to T3 conversion
T4 to T3 conversion issue
T4 conversion
T4 to T3 conversion problem?
Conversion t4 to t3
