I just put all my latest lab results in the calculator and said “YIKES”! What ratio should I be shooting for? This doesn’t seem right — and I sure don’t feel well.
Having the percentages really helps me understand just how low I am on B12 & D!
Thanks always.
- T4:T3 Ratio: 0.417
- Free T4: 1.25 pmol/L (0.82 - 1.77) 45.3%
- Free T3: 3.0 pmol/L (2.0 - 4.4) 41.7%
- TSH: 0.016 mIU/L (0.45 - 4.5) -10.7%
- Reverse T3, Serum: 30.5 ng/dl (9.2-24.1)
- C-Reactive Protein: 8.84 mg/L (0 - 3) 294.7%
- Folate-Serum: 19.2 ug/L (≥ 3)
- Ferritin: 96 ug/L (15 - 150) 60.0%
- Vitamin B12: 529 nmol/L (232-1245) 29.3%
- Vitamin D: 60.9 nmol/L (40 - 100) 34.8%
- A1c: 5.8 (4.8 - 5.6) 125.0%
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Hunny_BEE
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I think greygoose has summed it up really - a ratio is not a target.
A ratio might help decide what is wrong. And maybe, in time, you will see a ratio that seems to suit you. But even if you do, our bodies change over time and that ratio should not become a target.
It's not about ratios. With thyroid hormones, you need what you need. Some people need their both their FT4 and their FT3 high in range. Others are fine with high FT3 and low FT4? And then people like me are better off with zero T4 and high FT3. And all the different levels in between.
So, there is no ratio to aim for, there's just finding what level of which suits you as an individuel. Because we're all different.
I get kind of frantic (not sure if that’s the right word?) when I start feeling so lousy — so I try to look for more answers. There is so much information that it becomes a muddle in my head. I just know that I don’t feel well and no doctor seems to want to listen or investigate properly.
I think you feel rotten because you're under-medicated. Both your FT4 and FT3 could be higher. So could your B12. If I were you, I'd be asking for an increase in levo.
Yes, I agree. I started taking the B complex - I have to be careful with vitamins because they will make me nauseous or give me heartburn. more things are wacky since having my gall bladder removed.
I have an appointment at the end of the month with a new endo. I can anticipate that he will not like my low TSH. So I am trying to get some research together to take with me - hence the calculators.
OK, but if you start talking about ratios, you could be shooting yourself in the foot. Put that idea in their heads and who knows what will happen next!
i think my best best is to show him how terrible my numbers were when they put me on such low doses last year - and I am still trying to get back. Plus, I really do believe that the gall bladder removal has also impacted how I process everything.
I had a doctor that wouldn’t even test TSH except occasionally and I did great! Unfortunately, she is no longer in practice
Detox issues can be further impaired by common MTHFR mutations and all the crap that goes with Hashi such as as inflammation, weight gain, etc. Fat malabsorption will also affect Vit D absorption.
We know hypothyroidism invites insufficient gastric acid but it also invites slow moving sludgy bile impairing detox further. I still have my gall bladder but supplement pancreatic enzymes from time to time just because of the destructive impact Hashi has on our digestive system.
Can I ask are you located in the UK? I am in the US and I have a suspicion I will end up on the self- medicating route. So I want to start figuring out resources.
I think I need both T3 & T4 because when they took my dose down to 60 mg NP Thyroid both T3 & T4 went in the tank while TSH went up.
One grain, about 60 mg, of desiccated pig thyroid extract contains about 38mcg of T4 and 9mcg of T3, a ratio of around 4 to 1....so much less than your current 125mcg.
It's likely that the ratio of T4/T3 in NDT wasn't correct for you and the flexability of a T4/T3 combo will make it easier to adjust your dose but you need a guide to do this rather than randomly changing doses and crossing fingers!!
A full thyroid test done at 9am, at least an hour away from foods and drinks and 12 hours away from T3 and 24 hours from T4 - and importantly combined with how you feel - is a start.
Also vital is to optimise vit D, vit B12, folate and ferritin to support thyroid health.
TSH is a poor marker ( science proves) FT3 followed by FT4 are the important markers
Working from accurate labs you may find you need less T4 and a little more T3....but only change one thing at a time.
I have to admit ratios per se were not my main focus I relied on hormone levels combined with how I felt....medics tend to sideline the latter.
Unlike machines that roll off factory production lines and need to be calibrated to set points/ numbers to work correctly we are humans with all the variants that involves....so aiming at set ratios is not a guarantee of wellbeing!
To underline my point, I high dose T3- only my TSH and FT4 are on the floor and my FT3 is high....that's what works for me and allows me to function. My heart is healthy ((scanned) and my bones are strong...and I'm 78!!
My GPs were initially horrified by my decision but now accept that it's what works for my body because it didn't come off a factory line of identical bodies!!
We are all different and medics must have the courage to understand this.....mine trust me to take care of my thyroid health now and concede that I know my body best. I've lived with it for a long time!!
Rant over...and best of luck.
Let us know how you get on....we're all here to help if needs be.
No energy, 20 lbs of weight gain that has plateaued, zero exercise tolerance etc., etc.
I have been a fit and healthy person all my life and this change has knocked me for a loop.
I have an appointment with a new endo at the end of the month. I am hoping that he will be willing to work with me in raising instead of lowering my meds. And not freaking out about the TSH number as they always do. Finding the right thing to say to them is what I really struggle with.
There are very few endos where I live, most of them are in the same medical system here in my state (FL) and my primary care physician cannot change my dosages without the endo recommendation. It’s a mess.
However, there is a normal, modal, statistical value for T3:T4 found in large scale population studies which associate with being euthyroid and that appears to be 0.33 so while we may not know what our set points should be or ever were perhaps it makes sense to aim for the ratio most commonly associated with euthyroid health at absolute levels of ft4 & fT3 that are not too extreme….. I would rather aim for something than keep trying to second guess often conflicting signs and symptoms of hyper and hypo states from over or under medication.
Euthyroid levels are red herrings. You can aim for them if you like, but not certain they will make you well. Hypos are not like euthyroid people, our bodies are completely changed. None of the rules apply anymore. If my doctor started whittering on about ratios and euthyroid, I'd get up and walk out. It doesn't apply to me. What we should aim for is getting to know our bodies better and feeling well. The numbers are only a rough guide to that.
At the author of the calculator should I remove the ratio from it, to avoid people worrying that there's a value to aim for?
I think one of you admins has previously said it has some utility but perhaps it only makes things worse for us guys who are already overwhelmed with so much information, often conflicting.
We need to focus on symptom resolution, healthful living, not fall into the trap of "perfect" numbers. A trap I'm always falling into.
Half of me wants to remove it for the reasons you state.
The other half of me wants to retain it as it is much better to know it is being calculated properly than random calculator/spreadsheet/mental arithmetic approaches!
Is there any mileage in a halfway house? Something like retaining the functionality but requiring the user to press a button to display it (with suitable wording).
I could easily enough do that, but there's a can of worms. For example someone said to remove % from vitamin D. The assumption (for me anyway) is also that % ft3, ft4, etc should be aiming for the max, but that's clearly not true and indeed counter productive in some cases.
If you experienced admins could come up with a shortish paragraph along those lines "it's about symptom resolution, not overly simplistic numbers" then I could add that. I could come up with something and you guys tweak it, but it wouldn't be for a few days.
Something like (off the top of my head): "When looking at blood test results always remember that we're looking for good health via symptom resolution, everyone will have their own unique "best" numbers as we are all uniquely and wonderfully made and there are no "one size fits all" perfect blood results.
We're aiming for good health, not 100% on the various numbers or some specific FT4:FT3 ratio"
Some specific messages against a few of them might help
I don't want you to change anything. If there are percentages and ratios that I don't want to make use of then I can just ignore them. But someone else may find them helpful.
But the problem is that an excess of information and % less than 100% may add to the anxiety of less experienced members. Until very recently even I assumed we want numbers higher. I particularly thought that both fT3 and ft4 should be high in range, whereas it would appear, for some at least, is far more nuanced than that.
Focus on good living and symptom relief. Numbers are just useful data to suggest where changes might be made if things aren't optimal.
I can add a well worded banner message and other caveats without taking functionality/data away.
Thank you for ALL of your effort and caring that you have put into the calculator!
I am most assuredly not experienced in research or numbers and ratios but I do think seeing where my numbers fall on range are just another tool to help when trying to make changes. I instinctually understood that everyone’s requirements are going to be different and not that I am aiming to get my numbers at 100% on both T4 an T3 but more to see where they are with the current dosage that I am on and how it might change when (and if!) the endo will help me with adjustments in medication.
Again, I appreciate so very much all the helpful and abundant advice that this forum provides.
The trouble is that the percentages are very largely of use in trying to compare results for labs which use different reference intervals. Not so much regarding the results of a single person at a single lab. For that, you can just look whether the actual numbers have gone down, or up, and some idea of by how much.
Few seem happy at less than 50% FT4 and FT3. But 100% is definitely not the answer for everyone.
And those who actually take a combination treatment very often seem happy with their T4 being a bit, or a lot, lower.
Maybe you could put a note to that effect along with the calculator? So people are reassured to keep focusing on their individual health, but the ratio is there if wanted? Or something along those lines😀
Well, I'm not the right person to ask that, because I'm biased against ratios in the case of thyroid. But, I do think that Sneedle and helvella both make good suggestions, if it's possible to do that.
The ratio is interesting but can only be loosely helpful as applies mainly to people not medicating and supposedly with a healthy thyroid (very subjective because levels change through age, pregnancy, illness, etc). There are many reasons why our ratios change from this ‘norm’ when medicating.
However, our resident scientist diogenes says this about ratios …. ‘Though strictly FT4/FT3 ratios don't accurately show conversion, the ratio is good enough for general diagnosis. In health the ratio is around 3 to 3.5/1 with the vast majority having FT4 and FT3 in midrange.
On T4 alone, with no thyroid, the ratio for good converters should be about 3.5-4.5/1 (together with FT4 high in range or just above and FT3 in midrange).
With some working thyroid, the ratio of about 3/1 to 4/1 is about OK on T4 only.
For those who cannot convert, the ratio on T4 only is greater than 4.5/1 (with low-normal or below-normal FT3). In such cases giving more T4 simply raises the ratio still more and FT3 changes little. They therefore need T3 to cover the shortfall in treatment. Concisely, consider the patient's individuality before making a decision from these ratios. They are guides not dictators.’
Tania Smith says ‘Most people, even with total thyroidectomy, do not need to go outside of reference range to find an optimal FT3:FT4 ratio. Most thyroid patients find relief from hypo and hyper symptoms by adjusting their ratio within range by changing doses slightly up and down within this frame.’
FT3:FT4 ratio (FT3 divided by FT4)- you are aiming for a higher number signifying better conversion, with healthy controls having an average of 0.31-0.33 (normal TSH).
You can do it the other way around as well -
FT4:FT3 ratio (FT4 divided by FT30 - you are aiming for a lower number that signifies better conversion (normal TSH).
But whichever way you use, you need to ensure same measurement for both hormones 😉, and you can’t switch between because T3 has a different molecular weight than T4 (one less iodine atom) meaning conversion factors are different.
I suspect you feel crap because you look under medicated, and the amount you are taking isn't working effectively as being changed to elevated RT3, most likely by your highly elevated inflammation. The low Vit B12 and Vit D, and over range long-term average blood sugar levels will be negatively impacting meds further.
Thank you for this helpful information and more clarification.
- Bloods were drawn at approximately 8:00 AM
- Meds (125 T4/10 T3) we’re both taken 24 hours since previous dose. I messed up with the 12 hour gap for T3. So as someone else pointed out - my T3 is probably a false low.
- Last TPO 10 IU/mL was taken in 02/23 I have had differing opinions on whether or not I have Hashi. Both my mother and one of my sons is Hypo.
The inflammation marker is concerning. I don’t understand the cause or what to do about it. I am also concerned that the RT3 along with the low TSH might be yet another reason for the new endo that I am seeing at the end of the month to want to lower my meds rather than raise.
I have been more consistent with my D3/K2 supplement and added B complex.
Two things happened in the last two years that seem to have put me into a tailspin of a 20 lb weight gain, more fatigue and very low exercise tolerance:
- Endo lowered my meds from 125/10 and changed to 60 NP Thyroid. My levels TANKED and I felt really terrible. Free T3 1.7 pg/mL (2-4.4) and Free T4 0.63 ng/dL (0.82-1.77) TSH 8.61 uIU/mL (0.45-4.5)
- Gall bladder removal at age 67 which I believe has impacted my ability to process nutrients and meds.
So I have been struggling to get out of this hole and to make adjustments for the Gall Bladder removal.
125 T4 + 10 T3 equals a lot more than 1 grain of NDT, so your endo severely under medicated you.
However, now you're back on 125 T4 + 10 T3, I'm not so sure you need to raise any further because unless the reason for the elevated RT3 is removed, then raising thyroid meds risks elevating RT3 further.
The forum doesn’t discuss RT3 a lot because the reason for it happening can not be known. However, I think it worth considering because is driven by the deiodinase thyroid hormone converting enzyme 'D3'. This enzyme also works to deactivate T3 to an inactive form of T2. D3 does not differentiate between the two hormones but deactivates them congruently. Therefore, it is important to try reducing the unwanted inflammation and using supports such as selenium to aid positive conversion.
As you say FT3 is artificially low and if FT4 stopped being turned into RT3 then levels would raise.
Are you gluten free?
Have you got gut issues that might be impairing absorbtion?
Do you manage exercise, even if only gentle yoga?
Are you eating cleanly?
Getting Vit D optimal will help as is a great natural anti-inflammatory & modulator of the immune system, and optimal Vit B12 is vital for healthy nerve and blood cells but also as part of the iron - folate - Vit B12 = healthy erythropoiesis.
After having my gall bladder removed I went to a Gastoenterologist. She tested for “Celiac Disease Comprehensive” and quite a few other things such as allergies and nothing came back as positive. The only item that looked low but still in range was Immunoglobulin E, Total: 17 IU/mL (6-495)?
By gut issues, the only thing I can think of is the gall bladder removal which has impacted digestion and bile etc. Someone suggested bile salts … I will research that
I have a rowing machine and I have finally learned that I cannot exercise hard. It has to be much more “gentle” as you say, than I am accustomed to. Rowing and walking are my forms of exercise. The nutritionist that I saw yesterday suggested more resistance training (gentle) than cardio.
Eating cleanly: I need to consume more protein. I rarely eat out and we cook quite well for ourselves but I could eat more at breakfast and/or lunch. I am not typically hungry in the AM.
I will research the inflammation question and perhaps add selenium.
and if the ratio is stable for healthy thyroids across the variations implicit in large scale population studies and studies of euthyroid and LT4 treated cohorts then its potentially a far far better guide for treatment than just TSH. I would go so far as to say that if TSH is about 1.0 and fT3:ft4 is just over 0.3 then we are probably doing ok. Getting there will almost certainly need a small proportion of liothyronine for many people and perhaps could the best argument, along with unresolved symptoms, for getting liothyronine prescribed - because fT3:ft4 ratios around 2 are terrible!
Personally I aimed for the ratio that gave me the least or preferably no symptoms. So for me I need my ft4 & Ft3 in the top third of the range.Also note your C Reactive is up, inflammation marker. You might find going gluten free and some people need dairy free helps settle the system down. For me it was GF and addressing my B12. Made a whole heap of difference.
That's the crux of the discussion and i found the very well argued contributions compelling.With the two numbers expressed as a ratio you can figure out if your body converts t4 into t3 or not and an informed decision could then be made on dosage.
I am glad it helped you. I always do well on NDT 4:1 most people don't. With no thyroid and no gut problems or anything else it was perhaps easier for me than some.
When the difference is not too great, it won't make too much of a difference when calculating the ratio... but when there is a large difference in lab range (eg the much lower 7.9 -14 range) ... it makes a significant difference to the resulting ratio... rendering the fT4 :fT3 'ratio' pretty useless as a method of comparison.
For example :
take a result of
fT3: 4.49 [3.1 -6.8] ...... 37.6%
fT4: 18.5 [12-22] pmol/l........... 65%
this gives fT4 :fT3 ratio of 4.12
Now suppose that person had their fT4 tested on a platform using the [7.9 -14] range ,
they 'should' still get an fT4 result that was approx 65% through range , right ?
so that same person would now have an fT4 result of:
fT4 11.9 [7.9-14]pmol/l ....65%
But if you calculate that as an fT4 : fT3 ratio , you get a totally different answer:
fT3 4.49 [3.1-6.8]
fT4 11.9 [7.9-14]
fT4:fT3 ratio 2.65
2.65 is a significantly 'better' looking T4:T3 ratio than 4.12 ... but it's the same person, same blood , same day ... they can't both be right .
due to the many different ranges currently in use on fT4 testing platforms (and to a lesser extent fT3 testing platforms) we have a significant issue with calculating/comparing fT4:fT3 ratio's.
Even though the units used for all these fT4 ranges are the same (pmol/l) ....you can't compare a ratio done using results from eg. a [12-22] pmol/l range, to one done using results from a [7.9-14] range.
All of those fT4 ref ranges are in current use , we see all of them regularly on here.
(There is also one fT3 range in current use which is significantly lower than the others, has a top end of about 4 rather than the more usual 6 ish )
Therefore fT4:fT3 ratio's achieved by the nice simple method of "fT4 result divided by fT3 result" are no use, unless you know that the ref ranges used to get the recommended / acceptable ratio were the same as the ref ranges used for your blood test.
Well, I'm sure that's true. Although I'm no mathmatician (far from it!). However, I still say that ratios are useless as any sort of goal to aim for when taking exogenous hormone.
Yes, you would need to change the range for both hormones tats, or you are not calculating like-for-like.
There is no doubt range and ratios work together (just look at ubiquitination) and we each have our own T3:T4 set point but ratios have to fail as a diagnostic tool. How can T4-only medicaters be assessed alongside a 'healthy' population when exogenous hormone risks skewing HPT signalling anyway.
Tania Smith agrees too (if you haven't read this yet tats, you will love it 😁) .......... thyroidpatients.ca/2019/05/...
notwithstanding that we know we can't really compare healthy euthyroid ratio's to medicated ones .. my issue with ref ranges still remains . and it still presents a problem even if trying to compare fT4:fT3 ratio's between 'medicated' people.
"you would need to change the range for both hormones tats, or you are not calculating like-for-like."
"Both must be based on FT3 and FT4 from the same blood draw.
Both ought to be measured at a single laboratory, using a standard immunoassay for FT3 and FT4 on a single platform (i.e. Siemens, Roche, Abbott, and so on).
To make a ratio within this system,
1. First, the lab results must be expressed in pmol/L...... "
....... But i didn't arbitrarily change 'only' the fT4 range in my earlier example ....... it's a factual example of my last complete NHS blood test which had these ranges :
fT4 [7.9 -14]
fT3 [3.1-6.8]
~ same blood draw/ results reported at same time .... so i can only assume that they WERE done on the same platform ... ( unless they were using a different platform for the fT4 test and the fT3 test .. which seems unlikely as fT4 and fT3 ranges both changed at the same time in 2018) they were previously using [8-18] and [3.8 -6]
So an fT4 :fT3 ratio calculated from my NHS results is not comparable to other 'medicated' people who have results with eg fT4 [12-22] range ..... and mine is not the only NHS lab using the [7.9 -14] fT4 range ... (eg . recent posts about bristol NHS lab using it ... i can't remember what fT3 range bristol were using)
and ...... since it is also hard to find what ref ranges were used when researchers calculated fT4:fT3 ratio's , how can we ever know if we are really comparing like for like when looking at ratio's .. even when we ARE comparing 'medicated people to mediated people' ?
Yes, and what you highlight is only one negative aspect. Tania highlights other numerous.
I said ratios can't be used as diagnosis tool but having slept on it 😁, I think they can be useful but not in conjunction with ranges, eg only to view how high each hormone is within the range and in relation to each other. Maybe this is where diogenes advocates ratios 🤷♀️
yes .. i think that's the direction of thought i'm wandering towards.
i think it might make more logical sense to calculate a fT4: fT3 ratio's using "% though range" numbers .... rather than using the actual blood result, with all the complications that wildly different ranges can bring .
i imagine that the relatively recent [7.9 -14] fT4 range wasn't taken into consideration much by researchers so far ..and they would probably have chosen not to include any results using such a low range in their research calculations anyway , because it would complicate the issue .. but for those of us who have labs using that range , we need to be aware of how much it does affect the result of ratio calculations .
Oh my! I will have to take my time reading through all the responses. There is a lot to digest. It appears that the calculators have a “life of their own”! 😅
( I definitely made a mistake when inputting the units)
Hunny Bee. Honestly you are best to focus on your signs symptoms, temp and pulse rate first thing with blood tests to back up. Personally I forget the percentages they can be misleading and not always accurate.
There is too much reliance on blood tests on their own. The other day I found out the multiple assays used with new machinary the NHS bought in so bloods can be tested for multiple tests at the same time are not as reliable or as accurate!! The B12 tests in particular are inaccurate and only pick up a small percentage of B12 deficiency. The labs know this but don't know what to do about it. Shocking! Everything these days is done on the cheap and not necessarily for the better.
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