Has anyone else encountered massive differences between tests? My medichecks TSH result last week was 4.33 (range 0.27-4.2), but my NHS blood test yesterday shows my TSH at 2.71 (range 0.3-4.8). Not quite sure which one to believe 🤔
Both tests were taken before 9am, with no levothyroxine for 24 hours.
Interesting... could it be that you had been up and about longer before the NHS test as TSH drops rapidly or could it be linked to your menstrual cycle? There was a paper on here the other day about menstrual fluctuations and I think the outcome was not to test TSH between days 10 and 20 (with 1 being the start of your period) as it can lead to less reliable readings due to fluctuating sex hormone
goodness really? Even less reason to go by TSH. What a farce 😒
Prepare to be impressed! I found it 😅
Of course it could even be if you ate lots of thyroid blocking food the night before... soya, dairy, gluten etc etc
healthunlocked.com/thyroidu...
Direct to paper.... frontiersin.org/articles/10...
So thyroid blocking foods would lower the TSH? Or raise it?
I think in theory they should raise your TSH whilst lowering your free T3/T4's.... I have only experimented on my Sister and after a day of dairy and soya her TSH was 2.0 higher... that's the trouble with TSH it is very hard to create exactly the same test situation as hormones/ food/ sleep or lack off/ stress all play a part 🤷♀️
I will try your test as well, at my next blood draw. Would love to move my TSH up a bit to make the doctors happy!
Ah, experimenting was done on unmedicated Sister which likely makes her more sensitive? I think when medicated a suppressed TSH can be harder to wake up 😕
it only involved two women... so we need to be cautious about what it noticed .
but it's the best we've got until the endocrinology profession wakes up and notices that half the population have a menstrual cycle for half their lives~ and i dunno .. maybe decide to see what effect this has on the TSH level that they claim is so 'exquisitely accurate' that it can be used to control diagnosis and dose adjustment (and lives) of that half of the population .. (the same half that are most likely to need their TSH tested )
I hear ya! But 2 is a start and they do seem to understand that hormones affect each other so.... they also realise that HRT effects your Thyroid dose..... they'll just work it out and then conclude TSH isn't the best test after all! Then start all over again reinventing the wheel and maybe realise T3/T4 testing is a remarkably useful way to go 😱(screaming)
tattybogle so is there no research into the effect of things like mensuration, pregnancy or menopause on reliability and consistency of TSH testing? If that's the case it's shocking, has no one noticed that hypothyroidism affects vastly more women than men?
Yes it's a disgrace. I am at the point where I wish women had their own healthcare system. It seems women in medicine get absorbed into the standard male centric model. I would also like women to have their own education, business and banking and systems but that's the radical side of me not relevant to anything here....
well i couldn't say for certain that this is all there is... just 2 women.... and the 'menstrual cyle effect' was not even the original purpose of their observations , it was merely "A fortuitous circumstance, which occurred in the first patient reported here, led to the hypothesis that a robust TSH release by the thyrotrophs in response to high circulating levels of estradiol (E2) at mid-cycle may increase levels of TSH compared to other phases of the cycle. We report the two patients, because they could represent the classic tip of the iceberg."
.... but i've looked quite extensively and so has jimh111 , couldn't find any other mention anywhere..... if you can find anything else please let us know .... hey, if you find 2 more women's results to compare you could get a nobel prize for "doubling the scientific knowledge in this field"
I still can't quite believe it myself ...... it's equivalent to basing solar power industry figures on data that forgot to mention the sun disappears for half of every 24hours .
Your solar power analogy is exactly right
You have Hashimoto’s and very poor vitamin levels
So thyroid levels are going to hop around a lot until on optimal replacement dose thyroid hormones and optimum vitamin levels
Are you gluten free or dairy free
Thanks, I'm trying to work on my vitamin levels but have been set back by my latest set of gastric issues. Currently playing "stomach bug or food sensitivity" 🤷🏻♀️
I'm completely dairy free and will be trialing gluten at some point soon
There's few days between tests so TSH could actually have been a bit different anyway .
The two tests have different lab ranges / different methods , etc . so that adds a bit more potential for difference
Even with 2 samples taken at the exact same time run through the same machine , you would get a small % difference, they are allowed a certain % variation . so that adds a bit more potential for difference ,
The best you can do is assume its "something over 3 "
if it's for diagnosis ,GP will not accept a medichecks result as evidence anyway , they will go by NHS result .
if it's not for diagnosis , but for dose adjustmesnt then it doesn't really matter which is 'more' 'correct , as they both tell you you have room for a dose incresae if you want one .
dizzyarmadillo
I just want to point out that leaving off Levo for 24 hours has no effect on TSH, it only affects FT4 result.
What does affect TSH is time of test and certain food and drink can also affect TSH which is why we always advise water only before thyroid tests. Also if you have an infection or acute illness this can affect TSH.
Thanks, time of test was within half hour of each other and I had only water before hand.
I'm currently playing "stomach bug or food sensitivity" so maybe that's the reason 🤷🏻♀️
Eating breakfast before the test also lowers TSH so if by any chance you did that one day and not the other .. that would also affect TSH result ... The evidence for this effect was previously 'rubbish' , but not any more .... bmcendocrdisord.biomedcentr...
Thanks, I didn't eat breakfast either day before the tests 🤷🏻♀️
if you have issues with gastric problems /sickness /diarhoea etc this will be affecting how consistently you absorb the T4 from Levo from one week to the next .
this variation in T4 level would cause TSH to wander around a bit .
T4 level doesn't change TSH level 'on the day'..... but over few days/week it does .
what were Ft4 and Ft3 results on both tests
The NHS test didn't have T3 or T4 as the lab won't test them if TSH is in range. The medichecks results are below.
I see that you have high antibodies, that itself causes TSH to fluctuate wildly so it's no surprise there was a difference in the levels a week later.
yes I had a recent Medichecks test:
T4 - 28.9
An NHS test 1 week later:
T4 17.7
Similar ranges, both tests taken at same time in am on empty stomach, Levo the night before. TSH in my case similar in both (suppressed).
I was concerned as this is a big discrepancy and I’ve been stable on Levo for years, T4 normally around 19-21. Not sure which to believe but Medichecks have offered me a free repeat test.
My GP and hospital tests (not just thyroid) always come back lower than Medichecks, recent liver enzymes very different results !
My GP's phlebotomist filled a medichecks vial at the same time as doing my GP's vials. The results for fT3 were virtually identical.
I did the same test with blue horizon and GP's blood test and they differed widely.
As a result I use medichecks whenever I want an extra blood test as I know it will be comparable with the blood tests my GP is doing.
I can't comment on the accuracy of the TSH result as mine is always suppressed at <0.01
A sample size of one isn't big enough to draw any conclusions and I would be interested to hear if other people's experience matches this. Note it's important to do the private test at the same time as the GP's blood test, otherwise other factors could be influencing it.
hi, what laboratory through Medichecks carried out the test?
Eurofins County Pathology
I’ve recently had the same problem. My TSH was 8.73 from Monitor my Health and 0.93 from Medichecks both same ref ranges. I’m 68 so no hormones to speak of to make such a drastic difference.
Hi Greenfingers, can I ask did Medichecks use County Lab for your test too?
Luckily just found it, no it was Eurofins County Pathology.
I’m not sure I would have to check. I’ll have a look.
I had thyroid test done by Eurofins County Lab via Medichecks too, for the supplemental dose I was on, the level was a way higher than usual too.
Vitamin D discrepancy Medichecks vs GP
Recommended time between blood tests when upping dose? 
How can I organise the gap between meds and my blood test?
Test difference between NHS and Blue Horizon Medical
Do you need to have max 12h between t3 and test? 
