T4 and T3 in NDT are largely strongly bound on to thyroglobulin protein

[diogenes]

This chapter in a book shows quite clearly that in the intact thyroid, T4 and T3 are tightly bound on to a protein called thyroglobulin. Only when this emerges from the thyroid is the T4 and T3 released as such. This has profound implications for NDT use, by mouth. This is because the T4 and T3 will not be immediately available to being absorbed until the protein has been digested in the stomach and small intestine and the hormones released. Therefore the implication is that as regards controlled uptake of the hormones, especially for T3, there won't be the kind of FT3 "spikes" that occur when T3 alone is taken. This may explain the benefits of NDT (DTE) as a slow release application if someone is sensitive to T3 spiking. It supports the use of NDT and downplays the strength of the argument that the ratios of T4 and T3 are different from humans.

“Thyroglobulin Storage, Processing and Degradation for Thyroid Hormone Liberation”: A Comprehensive Guide for the Clinician

January 2019

DOI: 10.1007/978-3-319-72102-6_3

In book: The Thyroid and Its Diseases

Klaudia Brix, Maria Qatato, Joanna Szumska, Maren Rehders

[UrsaP]

Thank you diogenes the link does not seem to be working.

[diogenes Remembering in reply to UrsaP]

I put the DOI into Google and it came up fine.

[UrsaP in reply to diogenes]

OK will do that. Thank you.

[helvella Administrator in reply to UrsaP]

This is a direct link: link.springer.com/chapter/1...

[TSH110]

Fascinating, thanks for posting. diogenes , would this fact have any relevance to taking NDT sublingually - some here say it is pointless because the molecules are too large to get through the oral mucosa, but I do take it that way in the hope I get some calcitonin.

[LAHs in reply to TSH110]

I think by "by mouth" they mean you put it in your mouth and swallow the pill as opposed to it being injected. Regarding the sublingual method, you are right, however my little tin pot theory is that it all goes down the esophagus in the usual way just carried by the saliva. But as you point out, there are some molecules of some drugs that can be absorbed by the oral mucosa under the tongue.

[Hillwoman]

Very interesting diogenes . I note what you say about the slow release of protein-bound hormones in the gut, which I suppose could potentially be a problem for the people with autoimmune gastritis and low stomach acid production.

I remember your remarks on the forum some time ago, to the effect that mainstream worries about the T4:T3 ratio in NDT are nonsensical, because any excess T4 will just be deiodinated to RT3. In the light of this, do we still need to use the rationale contained in your final sentence when in discussion with the mainstream profession?

[diogenes Remembering in reply to Hillwoman]

The argument is quite simple. So long as you have enough hormone input, be it more or less T3 to T4, your body deiodinases will simply convert some T4 to more T3. So long as the sum of the T3 you take by NDT + the T3 converted from T4 is OK as regards blood FT3 levels, then the T4 level itself from the NDT no longer matters. There is no evidence that an in-range T4 is essential for adequate health. Some T4 may well be useful, but that is only because it may have minor positive effects which we know little about.

[Aurealis]

Thank you diogenes, to me, that’s exactly what NDT feels like; slow release T3.