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Thyroid UK
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How NDT content of T4 and T3 is controlled (USA)

I've just found out how in the USA at least and probably elsewhere, the T4/T3 content of NDT is controlled. Obviously raw thyroids will change in content batch to batch and I first thought that batches would be mixed to get the right hormone content. It seems however that to control T4 and T3 content in NDT, synthetic T4 or T3 is added to produce the right product. So NDT is NOT purely natural but is a mix of natural hormone + synthetic hormone.

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:O

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Well I have read replies of yours in the past where you have mentioned that it is not that natural as they have to use binders and fillers - or did I dream that ? :-)

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No, you didn't dream it. But, I did at least think the hormone bit was natural! I am incredibly shocked. Surely that's against the Trade Description Act, or something. Doesn't sound very honest to me.

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When were drug companies honest ? They obviously saw the gap in the market and needed to fill it - with fillers and binders and synthetic ingredients :-)

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My faith in humanity is utterly destroyed!

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It could be the same as a shampoo that is described as Organic. So long as it has one or more organic ingredients, it can be called Organic? Not very honest and rather misleading if this is true about Pharmaceutical NDT particularly as they deem other types as 'dangerous because you don't know exactly whats in it'.

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Well, not exactly the same, because NDT, in the beginning, had to be all natural hormone, because there was nothing else. But, it would seem, they've slyly slipped the synthetic hormone in there without telling anybody - much less changing the name!

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No wonder some people are still not good on NDT

Theres plenty of people so acutely sensitive to chemicals they simply cannot tolerate levo or T3

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OMG!☹️

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Just shows how everything is interfered with to suit the pockets! Thanks for sharing this diogenes Tagging linda96

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This is quite shocking and even more worrying as I get mine from Thailand so goodness knows what’s in it. I couldn’t imagine not being on it though as it has given e my life back.

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It is probably a very small amount added and I feel fine on ThyroidS - I assume the same is done to it. Stop the Thyroid Madness has a list of what is in it I can’t see why they would add things for the hell of it they do want to sell the stuff after all.

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It probably is small, but strictly you cannot call the product Natural Dessicated Thyroid from the hormonal point of view.

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What sort of % is natural and what synthetic I wonder. So to be NDT it must be 100% natural hormones - interesting.

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I noticed that one person in Thailand who was promoting the Thai NDT was looking for sources to get Turkey NDT - why would they do that unless of course their own was inferior. Stopped me in my tracks anyway, warning bells!

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Will this be the case with Thai NDT like ThyroidS, do you think? It certainly appears very uniform. I wonder what was done before the advent of synthetic T4 was NDT just less predictable in terms of hormone levels in it then? Is the addition a bad thing or something that might be beneficial to us?

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When control of NDT was less good pre 1980's there would be variation in content. This because up to then, the method of measuring T4 and T3 content was unsatisfactory.

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Shocking and disturbing! Thank you for posting.

Are you able to share how you came by this information? There was recently a change in the formulation of Nature-throid. I began feeling like I had on Levo and wondered if they had topped up Nature-throid with synthetic hormone. Told myself I was being paranoid.

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No I'd prefer it to remain anonymous. One has one's sources of info that need careful nurturing.

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Of course! :) I was just wondering if it were that type of insider information or something that a member of the public could learn more about, for example, whether some manufacturers are more guilty of this than others. It would add to my shock if it were an industry-wide practice.

Carry on nurturing those sources and thank you for the information and insights you share with us.

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I would believe that it is industry-wide as the alternative way of control by batch mixing would be difficult. For example, no batches might be mixable sometimes if none happened to be capable of giving there right answer when mixed. Then there would be no product to sell.

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Perhaps it is very much to our benefit then

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That's what struck me, too. Yes, they should declare it...but, it's also in our interests to have reliable doses? Not that excuses them. Seems all big corporates just skim along the wire.

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Just trawled through the ETA2018 abstracts. Didn't find anything of interest in respect of T3/T4. The most interesting thing I found was a paper on treating a hyperthyroidism case caused by eating sausage where thyroid glands had not been removed from the pig. Next time the pigs go to the abattoir there might be a special request ......

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Ah, "hamburger thyrotoxicosis". Bet you meant hypothyroidism.

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Nope. Hyper. Excess of T3. Munch munch.

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Apologies, my noggin must need sweeping out.

I've read of dangly moose thyroid glands being eaten, for a boost.

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Sounds yummy. Not. And from reading the sausage abstract I guess a moose thyroid would blow your socks off!

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Gimme the sausages....

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On second thoughts....I'm a veggie that eats thyroid extract 🤔

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Me too after 30 years too 😢

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Hey, SmBlThg, did you know that there is no Ham in a Hamburger and no Burro in a Burrito?

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There shouldn't be any mites in Marmite ;-)

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Right!

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My neighbour has pigs 😁

Interestingly as well, my horse has a swollen thyroid but the vet said that they don’t get thyroid problems so ignore. I find this hard to believe. If all your cells and organs need T3 then why wouldn’t this be the same in a horse? Otherwise why would they have a thyroid gland?

Sorry I digress...

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Weird. I understand thyroid problems are a growth industry for cats and dogs.

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It appears that adult horses can be hypothyroid without seeming to suffer significantly. However, there are quite a number of papers about thyroid issues and horses:

ncbi.nlm.nih.gov/pubmed/?te...

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Thanks for that Hellvella, my horse is in the hospital as we speak he’s very lack lustre and has muscle weakness to me I think it could be thyroid related as somenlarged. I will have a good yread of this.

Thanks again.

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A number of questions arise:

Is the added synthetic thyroid hormone itself pure? Or is it rather more like adding bits of liothyronine and/or levothyroxine tablets with all the excipients in there? Or somewhere in the middle?

Do they start out trying not to add any synthetic thyroid hormone and only add if proved not to be possible to get it right without?

Do any of the non-prescription products do this? Or do they let the content vary?

Does this get done by the producer of the Thyroid USP powder? Seems it must in order for the Thyroid USP to meet its standards. But maybe the tablet maker also has to make small adjustments?

Not expecting any answers, just mulling it over.

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Well that's a bit disappointing, they can't leave a good thing alone can they!

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Here is a little ray of hope. I am no great shakes at converting and I am on Armour NDT. My T3 to T4 ratio usually comes out as 3:1 (i.e. you need 3 T4 molecules to make 1 T3 molecule), this is the pig ratio not the human ratio of 4:1. So maybe the messing around is not too bad. Perhaps they get a batch of pigs that are too hot (i.e. very high T3) so they throw in a bit of synthetic T4 to balance it out - that's better than throwing out a whole batch of pig thyroid.

(Oh and pardon me Helvella, I know you know what 1:3 and 1:4 ratios mean, I was just being very explicit since many don't.)

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Diogenes ,

Thank You for this and many Honest valuable Information's you so Kindly Share with us . I am Shocked but Not Surprised . BIG PHARMA one way or another gets their BIG FOOT into Everything to Make It Fit . So that they can also Profit .My Big Concern is the patients that don't do well on synthetic and are dosing with NDT thinking they are getting what they Think they are getting . In fact NOT . Can this be the reason that many of late are having problems with their NDT dosing ? Where is the Credibility Honesty Transparency of the NDT manufacturers ??? They Owe it to the thyroid patients who are buying their NDT in good faith . Thinking they are getting Natural Porcine thyroid when infect they are getting mixture of everything and who knows what ELSE ????

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Can this be the reason that many of late are having problems with their NDT dosing ?

It was towards the end on the twentieth century that there was a lot of fuss about the consistency of desiccated thyroid products - and, for that matter, levothyroxine - in the USA.

If there was a changeover from solely using batch blending to adding small amounts of synthetic hormone, I suggest it was no later then then, and possibly much earlier.

That is, I personally doubt it explains anything recent.

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helvella ,

Thank you for your kind reply . If this was the practice from early on adding some synthetic T3 T4 to Porcine NDT. Why is it that it surprised me and many others who are under the belief that NDT is all Natural ? Wouldn't this have been publicized all along ? Please understand I'm not trying to be disrespectful . I'm just trying to understand why those of us on NDT where Not aware of this all along ?

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I'm going to buck the trend, and say that I'm relieved. To me, the more important thing is that it is consistent, which this achieves.

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I find this a sadly dishonest practice. People need to know exactly what they are taking, even if the intention is to make the pills have a uniform hormone content. Not everyone tolerates synthetic T3/T4. Even in such tiny amounts!

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Let's not be too "mentally insane" (as my children say).

Remember the initial, possibly valid, criticisms of NDT, when synthetic thyroxine was discovered, were all centered around dosage consistency. The medical community, believing that patients could achieve wellness with t4 replacement alone, rejected the unreliability of hormone levels in grains of NDT and embraced Levothyroxine for its majestic consistency.

So, in an attempt to mitigate that concern, if the manufacturers of porcine thyroid have found that addition of synthetic hormone can help regulate the dosages, can we fault them?

That seems rough.

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There is a lot of sense in that (see my earlier response). The issue seems very much to be about transparency, openness and honesty.

It would be good to know the ranges of synthetic hormones that are added and whether there are limits?

Some years ago during a major USA desiccated thyroid shortage there were reports of compounding pharmacies producing products consistently solely of synthetic hormones (and excipients) as "compounded Armour". That really was despicable practice.

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I agree, wholeheartedly, that deceit is bad.

But I'm learning to pick my battles. And if my choice is a consistently inconsistent "natural" product or a consistent bi-product, for my purposes (restoring hormone balance and achieving wellness), I choose the latter.

Would I prefer to live in a world where everyone told the absolute truth all the time? Yes.

That does not appear to be one of my options.

So, onward and upward, in our individual and collective endeavors to find that ever-lovin' and elusive 'balance' and share our discoveries along the way!

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I thought the same.

Adding trace amounts of synthetics to balance out a whole batch of animal hormone is one thing. But whose to say whether it becomes cheaper to supplement 50% of the hormone, or any other large proportion. We can't know where the line would be drawn.

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Sorry, but I don’t see a shred of proof. So, to me this is entirely conjecture/theory/rumor.

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If you mean that T4 and T3 adulteration is a rumor, I can only say that my source of information was a distinguished professor in America in thyroidology and I have no reason to disbelieve him.

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Did your source give any indication of the level of synthetic being added ? It is really worrying for people who cannot tolerate Levothyroxine , believing their NDT is without Levo - If they have any problems they will be searching for other causes, when it could just be the Levothyroxine. Of course the majority take it as a method of obtaining T3.

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That's an interesting thought. I wonder, though, if people who can't tolerate the levo are actually not tolerating a filler/binder, or if for some people T4 alone is an incomplete treatment.

For me, I started on T4 only. I felt better on T4 only than not on anything ;) but I wasn't *well*. I don't know that I didn't tolerate it as such, just that it was an incomplete treatment for me. (I know lots of thyroid patients who are just fine on T4 only, so there's obviously some variation there.)

Now, I'm not sure I've ever felt completely restored to health on NDT either ;) but I think it is maybe unrealistic to think that pills can replace the fine control created by a properly functioning thyroid.

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It will be a very small amount, if there is a small shortfall in T4 or T3 levels in a particular batch of animal thyroids. The product has to obey the US Pharmacopeia standards, and it seems that occasionally a batch hasn't got enough hormone naturally to do that.

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Surely then the batch should be discarded in those cases - or notification that it contains Levothyrone or synthetic T3 should be made clearly on the bottle - people are led to believe it is a natural product

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I haven't gone into this in detail so can only surmise. Natural T4 and T3 in NDT are chemically and structurally and actively identical to pure chemically made T4 and T3. So, as long as the synthetic hormone is of pharmaceutical standard (as used in T4 and T3 tablets) it seems to be deemed to be equivalent to the natural hormone and thus able to be used in this way. I personally have no pharmacological problems with this so long as the adjustments are small, but to claim the product is Natural Desiccated Thyroid (NDT) is highly misleading. That is why the new term is Desiccated Thyroid Extract to get around the fact it is not 100% Natural.

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So this leads to the conclusion that the main reason why people like me who do so much better on NDT than Thyroxine is because it contains T3. I should do as well on combination synthetic but have not been given the chance to try it due to it’s non- availability on NHS.

Thankyou for bringing this to our attention. I await replies to my questions to the manufacturers about this.

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I'm not necessarily saying that. NDT (or DTE) is a far more complex product than just T4 or T3. It contains many other substances, of which we are ignorant of the effects. Quite an amount of the natural T4 and T3 in the pig thyroid is chemically bound on to a protein called thyroglobulin. When you swallow this, it takes a while for the stomach to digest this and release the T4 and T3 from the protein. Only when this is done can that T4 and T3 enter your system. In a way, this means that part of the T4 and T3 you take is in a kind of slow release form. This might smooth the rate of takeup so that you don't get the "spikes" that happen with T3 especially after taking the pure hormone. There hasn't been a pharmacological study on this as far as I know, and I would very much like to see the progress of taking a) pure T3 and b) NDT compared in the rate of T3 uptake for equivalent doses.

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As far as T4 and T3 are concerned I don't think so. T4 is T4 however it is produced, ditto T3.

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With steroids there is a particular problem regarding where they come from. Several sources don't just contain the bioidentical substance, but other ones as well as impurities. Eg Premarin is not a bioidentical medicine because it contains other things than progesterone.

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😳

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I believe this to be rumor until I see proof otherwise or information that will allow me to actually assess the veracity of the allegation. This practice would not only be unethical, it would be a federal crime in the US.

Dessicated thyroid extract is not just ground up pig thyroids. It is a calculated process with tight and exacting controls. Mixing other drugs into an FDA regulated drug is illegal and would be a very high risk with a massive price to pay.

The allegation is also suspicious, since more thyroid cancer patients are educating themselves and learning from experience that T4-only treatment is not ideal for some 15-20% of thyroid cancer survivors, since they are no longer getting any natural T3 from their thyroids, with most being genetically poor converters. [And note that Cytomel supplementation is generally not properly administered.] Yet doctors are inculcated early on to believe otherwise about T4 and conversion. Perhaps the T4 industry is feeling threatened by patients wanting to live better lives.

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Simple answer. Ask the companies.

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This is the reply from Broda Barnes who detailed the manufacturing process in 1999. I asked them whether they had an update of the process and if they knew T4 is added to NDT

In response to your email, we do not know of any instance where

Levothyroxine is added to NDT.

Broda O. Barnes, M.D. Research Foundation, Inc.

PO Box 110098

Trumbull, CT 06611

(203) 261-2101 - phone

(203) 261-3017 - fax

brodabarnes.org

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Best to ask the manufacturers direct.

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I have done this and await responses

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I must say I have a logical difficulty with how using natural products BOTH T4 and T3 levels (absolute and relative to each other) can be controlled in every batch as directed by the US Pharmacopeia. It seems to me a tricky problem, because if you can correctly get the right T4 level, the T3 may be wrong and vice versa. The quality of the thyroid glands will probably differ continuously according to happenstance and also quality of product. Very tempting then to cut corners and add hormone to simply get the product in spec.

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One other hint is that the product now is usually called Desiccated Thyroid Extract (DTE) not Natural Desiccated Thyroid (NDT). The former wording gives scope for manipulation whereas the latter doesn't.

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