Please could you confirm if I'm a good converter, I've been feeling tired, cold etc recently so doctor arranged a TSH test (as you're all aware most won't do T3 & T4 🙄) and loads of other tests, the Medichecks TSH test result matches the NHS test result but I wondered if my symptoms might have something to do with if I'm a poor converter, however I'm not sure from these results and wondered if you could confirm either way please. I've also noted below my vitamin results.
Medicheck Results
Folate Serum 12.28 ug/L [ >3.89 ]
Ferritin 329 ug/L [13 - 150]
Vitamin B12 Active 143 pmol/L [37.5 - 150]
Vitamin D 105 nmol/L [50 - 200]
CRP HS 0.69 mg/L [0 - 5]
Antibodies confirm Hashi's
All tests were done as advised at 8.00 am before food, drink & medication.
Same brand of medication and I take 100 mg each day.
The accepted conversion ratio when on T4 monotherapy is said to be 1 / 3.50 - 4.50 - T3/T4 with most people feeling at their best at around 4 or under.
So to find your conversion ratio when on T4 only you simply divide your T3 into your T4 and I'm getting yours coming in at around 5.70 showing poor conversion.
No thyroid hormone replacement works well until your ferritin, folate, B12 and vitamin D are up and maintained at optimal levels and other contributing factors can be inflammation, any physiological stress ( emotional or physical ) depression, dieting and ageing.
Your ferritin is way over range - do you know the cause, what has your doctor suggested ?
Obviously having Hashimoto's AI thyroid disease throws a spanner in the works, as you are looking at erratic thyroid levels from time to time and a gland that long term will be of reduced capacity as this disease progresses.
Thank you for your reply. My ferritin has been high for some time but the doctors do not seem concerned about it when I have questioned it and the doctor didn't test for it in this round of tests.
The results from Medichecks for Folate, B12 & Vit D all appear to be optimal so I will continue as I currently do.
Do you think I may need an increase in T4 with being a poor converter?
No - you are already slightly over the range - your conversion isn't going to improve with more T4 and the logical first step is to drop some T4 thereby " making room " to take a small amount of T3 - Liothyronine making a T3/T4 combo.
The NHS does prescribe T3 but you need this to be sanctioned by an endocrinologist and there is generally a 3 month trial initiated with your Surgery consenting to picking " up the tab " if the trial is " deemed " successful.
Sadly obtaining T3 on the NHS is still a post code lottery with various CCGs throughout the country refusing new prescriptions and or limiting the amount to be prescribed which is totally ridiculous.
If, you can go into - openprescribing - and then - analyse - you can view by CCG and surgery how active prescriptions of Liothyronine are within your surgery and local area.
Many people on here are doing it for themselves as they can't get the help they need.
GP's hands are now tied and they can only prescribe T4 :
I think you need to find out why your ferritin is so high and your doctor should be concerned :
I don't take T3 so can't help with sourcing for you, but if you start a new post asking for PMs forum members can advise privately a safe source if you want to go this route.
I don't have a thyroid as I'm with Graves and post RAI thyroid ablation 2005 and I have found that Natural Desiccated Thyroid suits me best and now over 4 years into self medication with this full spectrum thyroid hormone replacement.
Hi pennyannie. Do you happen to have any study references to "The accepted conversion ratio when on T4 monotherapy is said to be 1 / 3.50 - 4.50 - T3/T4 with most people feeling at their best at around 4 or under."
Also, I'm curious as you're on NDT (so am I). Would you mind sharing your conversion ratio on NDT?
No, I'm sorry - no research papers per se, though I've read it several times in various books :
This " accepted conversion ratio " is only applicable for people on T4 monotherapy.
Various brands of NDT state different values of T3 and T4 per grain :
The ratio of my brand of NDT is roughly 1/4 - T3/T4 - with 9mcg T3 + 38 mcg T4 in each grain.
This doesn't translate to my blood test results on NDT as they are very much influenced by how well I convert the T4 component of the NDT and this is dependent on various factors including my vitamin and minerals being maintained at optimal levels.
My blood tests on NDT show a low suppressed TSH :
A T4 at around 25/30% through the range and much lower than when on T4 only ;
But my T3 is proportionately higher at around 90/110% through the range :
In fact it is as though my T3 and T4 have swopped positions :
I think the accepted conversion rate ratio is in one of Tania Smiths articles so may have reference pages at the bottom. However, can't remember which one though!
Thanks. I understand what happens when we take NDT re: reversed positions. So my ratio on NDT (FT4: 15.4 (11.1 - 22.0) and FT3: 6.62 (3.9 - 6/7)) would be 1: 2.3. What is yours - just curious...
Your result looks good - more to the point - how are you feeling ?
I'm now looking at the question and don' t know the answer -
but I'm ok and can't see the relevance if self medicating as I've nothing to prove ???
P.S. - ok, so thinking on - my results are pretty much like yours actually with a T4 running at around 25-30% and a T3 running at around 90-110% so I guess that makes me around a - golly - it's too early for me - !!!
P.S. Two coffees later - i fail to understand why I need this mental workout with my little pencil and paper - not to mention the confusion Ha Ha !!
I haven't felt well for over two years now. Just can't find the sweet spot. I was on 120 ndt at those test results and felt overdosed after 45 days. I reduced 5 days ago to 112.5. My symptoms are very confusing -- I don't want to hijack this thread tho!
Thanks Imaan. I think I understand the ratio done as a decimal (FT3 / FT4 as per Tania's articles). I struggle with understanding the other way around (FT4 / FT3). rT3 is not important.
When on Levo only most hypo patients tend to feel best when TSH is 1 or below with FT4 and FT3 reasonably well balanced in the upper part of their ranges.
Just looking at your percentage through range of FT4 and FT3 - 101% and 20.81% -show they are very poorly balanced, needing over range FT4 to produce just 20% of FT3, so your conversion is poor.
Hello SeasideSusie, thank you for replying I've not had a follow up call with the doctor yet, when I do should I try to get my levo medication increased or do I need to let him know I've had a private test which confirms I am a poor converter?
He may not know anything about conversion so you would have to explain about how T4 needs to convert to T3, etc, and hope he is open minded enough to listen. Anyway, your GP cannot prescribe liothyronine, this has to be initiated by an endo who should give a trial of 3 or 6 months if he agrees it's needed, then if endo says you should stay on liothyronine the GP would then take over prescribing. So you would need a referral to an endo who understands about this and is willing to prescribe T3.
Thank you for the explanation, hopefully when I speak to the doctor I will be able to articulate the advice you have given me to get back on the road to being & feeling normal 😊
I'm not keen on T3 / T4 ratios or describing people as poor converters. The rate of conversion depends upon fT4 level (increases as fT4 falls) and TSH which stimulates conversion.
However, your fT3 is rather low and you have some symptoms which may or may not be thyroid related. More importantly a high normal fT4 is associated with increased risks of cancer, cardiac disease and shorter life expectancy. So, I would push hard for your doctor to prescibe some liothyronine. Just a little (e.g. 10 mcg) should raise your fT3 and allow fT4 to come down (with a lower levothyroxine dose).
Hello jimh111, thank you for your reply much appreciated, its a lot to take in and I will approach the subject when I have the follow up call with the doctor, I will make notes before the call so 8 can get everything straight in my head 😊
Thank you for the information, I'm originally from Yorkshire but now live in Derbyshire 😁 I will email for a list of recommended thyroid specialist endocrinologist and doctors who will prescribe T3 and take it from there if I have no joy with my doctor 😊
Re your high ferritin result - I struggled for years with low ferritin levels, and then post-menopause they went through the roof. I eventually found a doctor who suggested that donating blood might bring the levels down, so now I do that once or twice a year, and it seems to have worked!
Hello, just something else to consider given your most recent Thyroid blood test. As the FT4 is over the range and TSH is low, it is possible that this reduces the conversion from FT4 to FT3 . In other words the pituitary glad sends a message through low TSH to your thyroid glad that your body does not need more T3, so you end up in a situation where you have more than enough FT4 but not enough is converted to FT3 so, may be it would be good to reduce slightly your T4. This should increase the TSH and as TSH increases we see an increase in the conversion rate from FT4 to FT3. Just remember that any change will not produce instant result, but it will take a bit of time for the this to work through the body's various channels. With thyroid hormone, more is not always better. I had a similar problem and reduced my T4 by 12.5 mg and seen a good increase in my FT3. Of course adding some T3 could also help, if this option is available to you. I hope that this helps and good luck.
Sometimes poor conversion is genetic. I did a thyroid genetic test and found I had mutations on both DIO snps which affect conversion. My functional doctor says if the NHS endos try (for the millionth time) to get me off my T4/T3 combo therapy that I can show that and they generally accept the need for combination therapy.
It was also really helpful for understanding other genetic factors which affect the creation and transportation of thyroid hormone in my body so that I can amend lifestyle to help ameliorate the impact of unhelpful genetic mutations. I’ve linked below to where you can see a sample copy of the report in case of use. Not cheap though think it was about £300 and not sure if you have to do through a registered provider.
Also I’ve found Dr Josh Axe helpful if you can’t access private healthcare. His book Ancient Remedies has recommendations in there for how to treat the root cause of lots of illnesses based on Traditional Chinese Medicine/functional approaches. I haven’t read it yet (it’s on the list) but I heard him talk about it on the Dr Will Cole podcast The Art of Being Well.
There’s another things you can do lifestyle wise that can support. For me, taking ashwaganda everyday has seemed to (I can’t say definitely/scientifically) improve my T3 levels hugely. Astragalus is another herb that is used in traditional Chinese medicine to help with thyroid also. Though often it’s recommended to use these under supervision of a functional/TCM specialist. I don’t have Hashis so don’t have the autoimmune element to contend with however.
Thank you for all the info, I will re-read it over the next few days along with all the other advice and make a plan ready for my follow up call with the doctor 😊
No you are not - your conversion rate is 0.175. 0.25 is the middle number. A result under 0.25 is poor - the lower the number the worse the conversion. A result over 0.25 is a good converter - the higher the number the better the conversion.
Optimal FT4 and Low FT3. I would say that you've got some RT3/reverseT3 and FT3 us being blocked from being used. You need to look at your zinc-copper-ferretin aka levels need checking, and seeing as your ferretin is high I'm guessing you're zinc is low, maybe High cortisol with possible adrenal fatigue. That's where I'd start so you're FT3 will balance up if my suspicion is correct Hope that helps
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