I started T3 nearly 3 months ago & have had a recent blood test to check my levels. My endocrinologist is concerned that my TSH is now suppressed & could do long term heart & bone damage, although I am feeling generally better on the hypothyroidism symptom side of things. I think when I have my apt, he may be reluctant to continue me on the T3.
I have hashimotos, I am gluten free, I am on 100 levo & 15 T3 (5g 3 times daily) All my vitamin results came back good (listed in previous post).
Test was done at 9am, before food, last dose T3 at 8pm day before & last dose levo at 8am day before. I was not talking any biotin containing supplements for at least 7 days prior to the blood test.
My latest results are:
TSH - 0.04 mU/L (0.27 - 4.20)
T4 - 12.9 pmol/L (12.0 - 22.0)
T3 - 4.5 pmol/L (3.1 - 6.8)
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RosWel
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PLEASE don't worry about suppressed TSH once you are on lio. It's normal.
There is a world of difference between having wildly high free T3, suppressed TSH and not being on thyroid meds - which is dangerous - and having in-range T3 and suppressed TSH because you are hypo and taking T3 meds .... but sadly this essential difference is often too subtle for medics who should know better!
It would be worth you having a dexa bone scan to re-assure you and your endo that your bone density is fine - and have as a benchmark for the future - and if you google some of diogenes 's posts you will see that a proper thyroid research scientist (that is who diogenes is) isn't concerned about low TSH and there are research papers to support him x
ok - by putting the name in blue I thought it was pretty clear I was suggesting the poster check out DIogenes' posts on this site, but accept it could have been even clearer ...
Hope things all right with you in France, GG, and Macron doesn't lock you down like before in the new year
If he is 'old school' you might find that he knows more than the 'modern endocrinologists. I hope he is able to relieve your clinical symptoms and return youto 'normal' health.
Thank you! That’s very helpful! Before I was on T3 my blood pressure was through the roof, so I feel that would be more likely to damage my heart health long term. But what do I know 😩 I will defiantly look up Diogenes (not the Greek god) & go to my apt with some knowledge. thank you!!
You are unlikely to suffer heart and bone problems with these results. However, having a low TSH like this can lead to a down-regulated axis, meaning your TSH remains low. This would reduce your T4 to T3 conversion rate giving low tissue T3 levels. T3 does not always suppress TSH, it depends on the overall fT3 / fT4 levels. If possible try reducing your levothyroxine or liothyronine dose and see how you go.
You may have to stay on this dose to feel well but try to manage on a slightly lower dose. Having a very low TSH for a long time has undesirable consequences unfortunately.
I’m confused. jimh111 you are saying that the posters endocrinologist is right to be concerned about suppressed tsh? Other posters here eg diogenes aren’t so concerned about suppressed TSH provided T3/t4levels are in range?. I have a very suppressed TSH though all my other levels are within range. Will this be harmful for my bones? What’s the evidence?
A slightly higher TSH is beneficial for conversion of T4-T3, but medicating T3 not only reduces TSH but offsets the loss in the converting process's . This is something endos fail to acknowledge.
Some members have skewed thyroid signalling that many endos also fail to understand. Therefore, what jimh111 suggests may be beneficial to some but for others, their years of previously undiagnosed or mismanaged hypothyroidism may have already resulted in some form of TSH down-regulation.
It is individual and the O/P’s FT4 level is already fairly low (which often happens when we introduce T3 meds) but reducing meds may risk inducing the reoccurrence of hypo symptoms and still fail to raise TSH. Low thyroid hormone levels have been implicated in both poor cardiac & bone health. A Low TSH alone has not. There is no evidence.
RosWel
If you feel well then these labs are good. Your TSH is expectly low and thyroid hormones are not over-range so will not be promoting osteoporosis or cardiac issues. A Low TSH is of no concern regarding bone or heart issues as long as thyroid hormones are kept within range. We require adequate thyroid hormone amounts to promote good bone & heart health.
If you are still symptomatic you may require a dose raise which risks reducing TSH lower, and this is one of the main issues hypo members have with their endos/GP's when medicating meds incorporating T3.
As in everything, the individual response to any treatment is exactly that and there are no hard and fast answers that suit everyone. As for low TSH being harmful on treatment I have an anecdotal story of my wife now 82 years old, who has been on T4 for over 50 years with almost undetectable TSH over all that time. There's no sign of osteoporosis and the occasional AF episode we deal with by slightly lowering dose for a short while. I'm sure she's not unique in this. The great thyroidal sin is diagnosing by category and not face-to-face individual assessment. That is the discipline's failure to grasp.
What I am saying is that it is best to avoid a very low TSH if you can because long term supression leads to a down-regulated axis with follow-on consequences of impaired T4 to T3 conversion. The important words are 'if you can'. Many patients need higher doses of thyroid hormone, especially T3, that lead to a low TSH. They need this to have a life.
Other patients have a low TSH because their axis has been down-regulated by previous high doses or thyrotoxicity during Hashimoto's or Graves'. Their TSH can be low even though their fT3 and fT4 are perfectly average. It's my view that the consequences of a down-regulated axis are completely ignored by the profession. It reduces T4 to T3 conversion cruically in tissues that rely on it, tissues such as the brain and skeletal muscle. So, I always advise fellow patients to try and recover without their TSH going low - if they can.
Note I usually avoid the term 'suppressed TSH' except when it is truely suppressed by high fT3 or fT4. Many times TSH is very low due to a down-regulated axis, depression or serious illness. In these cases it is not suppressed.
In terms of safety when TSH is truely suppressed it is associated with increased risks. We can see this in this study academic.oup.com/jcem/artic... which looks at patients diagnosed with primary hypothyroidism on levothyroxine. This study also shows that even a mildly elevated TSH is associated with much higher risks - doctors never point this out!
My comments are consistent with the advice from others, a 'suppressed' TSH is not as harmful as claimed. In many cases the TSH is not 'suppressed', it is subnormal, the pituitary is failing to secrete as much TSH as it should. In short, try hard to get better with a TSH that isn't too low, if you can't don't worry claims about the effects of a 'suppressed' TSH are greatly exaggerated (and not backed by evidence). For many of us having thyroid therapy than enables a reasonably normal life with the ability to exercise and keep fit greatly exceeds any putative risk arising from a 'suppressed' TSH.
According to Tania Smith (link below) "The primary regulator of D1 and D2 beyond the thyroid gland is not TSH." So while TSH does regulate the conversion of FT4 to FT3 by the thyroid gland it does not determine conversion in most other tissues.
"Rather, deiodinases are most powerfully regulated by thyroid hormone levels in blood and their level of signaling in receptors:
D1 is upregulated by higher-normal or high T3.
D2 activity is enhanced by lower-normal or low T4."
It is correct in the sense that thyroid hormone levels are the primary regulator of deiodinase activity. This diagram gives a good overview thyroidmanager.org/wp-conte... (you will have to register for free to get access). Essentially D2 and D3 control local and circulating T3. D1 takes over as hormone levels go high, it's purpose is thought to be to avoid thyrotoxicity and recirculate iodine.
This is how things work in a healthy person. However, when there is severe illness or famine the body needs to slow down and I believe this is signalled by TSH. A lower (and less bioactive) TSH reducing hormone secretion and T4 to T3 conversion. I explain this process in this webpage ibshypo.com/index.php/tsh-r... .
Sometimes however TSH remains low when it shouldn't do, when it should be normal. The result is a form of hypothyroidism with apparently 'normal' (but low) hormone levels and secretion of TSH with reduced bioactivity. I give some real examples here ibshypo.com/index.php/subno... . RosWel may fall into this category and need L-T3 therapy to get well.
Many thanks for your response. There's a lot been referenced so I need time to do my homework on it. I hope that your input has been helpful for RosWel.
I am not convinced that TSH is as influential as you believe, nor that having a low / suppressed TSH is as detrimentally far reaching as you describe. As many of us have such a TSH, this is an important question. For the moment I'll quote one more thing from the link I provided which would seem to be at odds with your version:
"Deiodinases co-regulate TSH concentrations. T3 signaling in the hypothalamus and pituitary is affected locally by the tissue-specific behavior of D2. TSH does not represent deiodinase activity and T3 signaling levels elsewhere in the body, especially during illness."
jimh111 radd diogenes janeroar thank you all so much!! Very interesting to read about. I would imagine in my case I would be better off on the doses I’m on now, as before I started T3 my blood pressure was high (178/106 average) which would also be detrimental for my heart health long term. (As a slim, healthy 32 year old it shouldn’t be that high). I will discuss all this with my endocrinologist at my apt hear his thoughts too, hopefully he agrees not to reduce my doses as it’s the best I’ve felt in years.
You are on 100 mcg L-T4 + 15 mcg L-T3 which equates to 145 mcg L-T4 which is not a high dose. Also your fT4 - 12.9 pmol/L (12.0 - 22.0), fT3 - 4.5 pmol/L (3.1 - 6.8) are certainly not high. Hypothyroidism causes high blood pressure, so your clinical response is an excellent marker for your thyroid status. Certainly a much better marker than TSH which is not reflecting your hormone levels. Stand your ground.
Thank you! I’m making notes to take to my appointment ☺️I spent 7 years having cardiology appointments due to high blood pressure, so now T3 has resolved that, low TSH is the least of my worries.
There are a number of trials I'd like to see to verify the role of TSH along with a project to measure TSH bioactivity in this patient group. (TSH bioactivity can only be determined in a reseach setting, it involves observing the action of TSH on thyroid tissue in the test tube).
I'm familiar with the text you quoted and struggle to understand it, I think she got a bit muddled, her communication is usually excellent. If I take a stab at the meaning ... D2 activity in the hypothalamus and pituitary is pretty constant whereas peripheral D2 is subject to various influences (including TSH I would claim!). The pituitary and hypothalamus want to know how much T4 is circulating so they need to convert it to T3 at a fairly constant rate. Peripheral tissues need to regulate local T3 levels to respond to various challenges such as exposure to cold or tissue injury. Thus, her final sentence about TSH not (always) reflecting T3 signaling levels is correct.
This is the point I'm making the whole regulatory system relies on secretion of TSH being 'correct'. i.e. the right amout of TSH with appropriate bioactivity for the circumstances. If the axis is down-regulated or TSH subnormal due to chronic illness or depression or whatever then there will be hypothyroidism with a TSH that is not elevated.
In my very uneducated opinion, this is what I thought. But then my endocrinologist suggested the opposite due to my “suppressed TSH”. I think he’s forgotten how high my blood pressure was before I started the T3. So I hope he doesn’t suggest to reduce anything.
I think what your Endo needs to do would be to trial you on T3 twice a day rather than 3 times a day. This would bring your TSH nearer normal. We all aim to have a healthy persons TSH of about 1.00. I would be arguing that point with your Endo. They shouldn’t stop prescribing. They should help you manage your medication to get optimal results and for good health and well being. I was on T3 three times a day when I was regularly going the gym once my under medicated situation was resolved. However, when I stopped the gym due to covid everywhere I had to reduce to twice a day. I feel fabulous these days and no issues. I’m also on liquid Levothyroxine. I have Hashimotos and DIO2 gene positive meaning I’m a poor converter.
My TSH was suppressed but now is just within range 0.64(0.35.5.50) my T4 and T3 levels are midway through the ranges after leaving a gap before medication ingestion and before the blood draw. I’ve never felt so healthy. So, it can be done keeping your TSH at the lower end of normal on T3 plus T4 Levothyroxine combined treatment.
I am feeling ok most of the time thank you. Unfortunately I still get days of fatigue. Tends to follow either a period where I’ve been extra busy or a very tiring day. For me the energy from the levo seems to take ages to build up again. I probably would be better on T3 only, but who knows.When I took 2 doses it was midday ish and 11pm ish.
But now I take 5, 2.5 and 5 at midday ish, 5.30pm and 2-4am when I wake. Does seem to help me have a bit more energy in the mornings.
Oh good. I am the same on T3, just the odd day of fatigue, not a constant need to lie down!Such a simple tweak to just change the timings of my doses, so definitely worth a try. Then you.
Oh thank you!! I didn’t even think that altering when I took the T3 would change my TSH levels. When do you take your 2 doses? I’m guessing it’s best to space them out as equally as possible? I’ll have to get creative with how I brake these tiny little pills 😂
Hi. No, you don't have to space them out equally. Our natural thyroid hormones have a daily rhythm. We need more in the morning than we do in the evening and overnight. Load your doses to the earlier part of the day.
I space mine every 7/8hrs every day. I was informed by my very senior private only Endocrinologist that T3 lasts about 8hrs but does have a 1/2 day half life also. If you are a poor converter of Levothyroxine it makes sense to take T3 every 8hrs or so. Otherwise you’ll have a dip and feel tired or lacking in energy. I cut my 20mcg tablets into quarters with a scalpel. My tablets snap quite well and don’t crumble. Just dab your finger on any crumbs and put on your tongue. Don’t miss any and don’t fall into the trap of cutting another tablet to make up for lost bits. You need to keep your doses as equal as possible. Our bodies don’t like ups and downs. It’s all about balance and balancing those hormones!
8 hour spacing has proved to be way too long apart for me. It takes a while for the new dose to peak so it's longer than 8 hours really and is giving swings during the day. I currently take mine at 8am, 2pm, 7pm. But I'm looking to bring that 2pm forward to 1pm shortly and try that. I can feel myself dipping before I take the 2pm dose.
It's quite regular to find T3 patients taking it every 6 hours during the day. Some even closer together. Overnight doesn't seem to be a problem. I'm still experimenting and haven't got to my optimal dose yet. But I do know the the timing is currently not optimal.
You may need your FT4 level higher. But some of us want our FT4 levels lower and our FT3 levels higher because having higher FT4 can reduce our T3 conversion. So once again, nothing is certain. We are all different.
From my experience, you are taking a lot of T3. T3 is four times as strong as T4. So, you are taking the equlivent of 60 T4 that is added to your straight T4 dose. That said, there is some controversy about how much damage is caused by a very low TSH. You might try to reduce your T3 a bit and see what happens to your numbers and your lived experience.
playtime2 thank you both. I’m pretty sure it’s a fairly low dose as my endocrinologist wanted to start me at the bottom & see if I needed more. My conversion is pretty bad, hence needing the T3, so I certainly feel better on it.
That's nothing like a high dose! There are people living nicely normal lives on 75mcg T3 a day. I'm currently on 45mcg a day and not there yet. Don't scare people off T3 by saying a dose is high. We need what we need.
Blood tests were only introduced when levothyroxine (T4) was 'new' .
Before that (from 1892) we were diagnosed upon our clinical symotoms alone and given a trial of the oldest replacement hormones which is called NDT (natural dessicated thyroid hormones) made from animals' thyroid glands and contains all of the hormones a healthy thyroid gland would do. So from 1892 lives were saved without blood tests but the skill and knowledge of all doctors who prescribed NDTs.
Unfortunately in the UK it was removed (I believe it may now have been reinstated) causing panic amongst patients whose health was good.
The 'professionals' also withdrew T3 due to its ridiculous cost but it, too, was reinstated but I think it can only be prescribed by an Endocrinologist now.
The endocrinologist is possibly nervous about your results as I think they believe we could have a heart attack if TSH is 'too low'.
Thank you! Very interesting to read. & a crazy thought of being medicated based on symptoms alone!As my blood pressure was so high before I started T3 (& I was even send you a&e as they thought I was going to have a heart attack) I assume the risk with low TSH may be less than higher TSH, but also high blood pressure?
I’ll remind him what a state I was in before I started the T3!
T3 was a life-saver for me and it resolved all of the unpleasant clinical symptoms I had on levo - especially super-fast heart beats. My whole body became relaxed with T3 and I felt well again.
On levo only I had severe (during the night) palpitations that caused me to wrap ice-cold towels I kept in the freezer, around my neck, to try to reduce palps and I also sipped ice-cold water at the same time.
On T3 my body is peaceful, normal heart beats and have no palpitations and I feel well.
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