I was diagnosed with an under active thyroid in 2018, after years of symptoms (mainly fatigue, dizziness and nausea). GP ran a full thyroid check after a scan on my neck for something else showed that my thyroid was inflamed. Tests came back showing antibodies (so I assume Hashimoto’s?) and I was monitored for 6 months - by 6 months my TSH had risen to 20.5 and my T4 down to 10.8 and I was started on 50mcg levothyroxine and after another few months moved up to 75mcg levothyroxine and I have been on that ever since.
I still don’t feel well though and despite being under active my symptoms have always been both those of under active & over active- in fact my GP said to me he was surprised as he expected me to be over active because I don’t put weight on easily and I am often jittery and anxious.
Every time I have a blood test I expect it to be out of range because I feel rubbish (tired, nauseous, dizzy, gastro issues, anxiety). But it’s always within range, though perhaps my TSH would benefit from being a bit lower (TSH - 2.59, T4- 19.8 , T3- 4.27 in December).
I’ve recently been unwell following a covid then respiratory infection. I had by blood tests run again and this time, although my TSH was normal (2.49), my T4 was slightly raised (21.9). My GP is monitoring it for now.
I had been considering asking to increase my levothyroxine to try to reduce my TSH, but with my T4 now high I’m not sure that I should or that me GP will let me - and given my jitteriness and anxiety maybe it’s not a good idea? I’m currently finding it harder to keep weight on, could that be due to my T4 being a bit raised?
Also wondering if all my problems are simply because I always get prescribed Teva brand levothyroxine and I’ve seen that that can cause issues? I have not really felt well since the first few months when I was initially treated and felt the benefit of the medication, but since a few months in I’ve felt not right despite always taking my medication. Or maybe it’s all perimenopausal symptoms now, as I’m 46. Or post covid.
Anyway, just off loading really. Thank you.
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MrsSFL
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can you confirm if you have been taking your levo dose as usual on the morning of the blood tests .. or if you wait until after the test to take that days dose ? this affects fT4 level .
Also what time of day are the blood tests taken ? TSH result is affected by time of day .
Can you add the lab ranges used for those fT4 and fT3 tests please
I always take my medication first thing, so around 7am. When I do a blood test it’s around 10 or 11am, and after I’ve taken my medication.
I have an NHS blood test for TSH and T4 once a year and also pay for a more thorough Medichecks test once a year. Their ranges are slightly different:
NHS - T4 range 11-20.2 pmol/l (no T3 range as they don’t test me for that)
Medichecks - T4 range 12 - 22 (so I guess by this range my latest NHS T4 result of 21.9 is just in range) and T3 range 3.1 -6.8.
I currently weigh around 58/59kgs. Usually I am about 60/61.
Vitamins may well be contributing to my symptoms, I’ve been low in D3, B12 and folate in the past, though are now in normal range according to my GP blood tests. My latest results, from early Jan are:
D3 - 78 mol/l (range 50 - 150 nmol/l)
B12 - 444ug/l (range 197 - 771)
Folate - 10.4ug/l (range 3 - 20)
Ferritin - 55ug/l (range 13 - 150)
I do take supplements but not always consistently until recently so I will look to keep up with supplements to try to improve my levels.
I’m on Teva brand of levothyroxine - I will ask my GP if I can try a different brand.
ok so ~ it gives a misleading T4 result if you take the days levo before the test.
this just measures the peak in fT4 level as a result of the Levo being absorbed all at once from the gut . usually between 2-4 hours after taking it , so at 3 hrs your fT4 is going to right up there,, but that is not the level of FT4 you have all day.
A more representative method for testing the 'true' fT4 level consistently is to delay taking that days tablet until after the blood test .. this is accepted as best practice , but most GP's will not be aware of it . hindawi.com/journals/cmmm/2... "...for FT4 after taking their daily dose of levothyroxine (L-T4) had different readings because of interindividual differences in pharmacokinetics and metabolism. Therefore it is important to probe a person already using L-T4 on a fixed time of the day before the intake of the daily L-T4 dose. For practical reasons, this can be done shortly upon awakening (i.e., prior to the ingestion of daily dose of L-T4) in the early morning between 07.00 h and 10.00 h....."
So your 'real ' FT4 level is not as high as it looks on your tests ,, if you test correctly next time it will be lower .
And this could be part of the explanation for your TSH still being relatively high when you would expect t to be much lower given the high fT4 level.
The TSH of over 2 suggests you perhaps do need a dose increase in levo ,, and when you test FT4 correctly that may show there IS room to do so , even though you current fT4 result 'looks like' there is not.
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using ranges from different labs ~ fT4 / fT3 results can ONLY be interpreted using the lab range that came with the result . (eg if the same sample had been tested at the other lab who used a testing platform made by different manufacturer , the 'result number' would have been a different .. although the" % through range" ought to be similar) . useful calculator for converting results into '% through range' so you can compare fT4/ fT3 results done using different lab ranges . thyroid.dopiaza.org/
Hashimoto's affects the gut and leads to low stomach acid and then low vitamin levels
Low vitamin levels affect Thyroid hormone working
Poor gut function can lead leaky gut (literally holes in gut wall) this can cause food intolerances. Most common by far is gluten. Dairy is second most common.
A trial of strictly gluten free diet is always worth doing
Only 5% of Hashimoto’s patients test positive for coeliac but a further 81% of Hashimoto’s patients who try gluten free diet find noticeable or significant improvement or find it’s essential
Similarly few months later consider trying dairy free too. Approx 50-60% find dairy free beneficial
Hashimoto’s and leaky gut often occur together
Both dairy and gluten are inflammatory foods
A strictly gluten free diet helps or is essential due to gluten intolerance (no test available) or due to leaky gut and gluten causing molecular mimicry (see Amy Myers link)
Changing to a strictly gluten free diet may help reduce symptoms, help gut heal and may slowly lower TPO antibodies
Trying gluten free diet for 3-6 months. If no noticeable improvement then reintroduce gluten and see if symptoms get worse
The predominance of Hashimoto thyroiditis represents an interesting finding, since it has been indirectly confirmed by an Italian study, showing that autoimmune thyroid disease is a risk factor for the evolution towards NCGS in a group of patients with minimal duodenal inflammation. On these bases, an autoimmune stigma in NCGS is strongly supported
In summary, whereas it is not yet clear whether a gluten free diet can prevent autoimmune diseases, it is worth mentioning that HT patients with or without CD benefit from a diet low in gluten as far as the progression and the potential disease complications are concerned
Despite the fact that 5-10% of patients have Celiac disease, in my experience and in the experience of many other physicians, at least 80% + of patients with Hashimoto's who go gluten-free notice a reduction in their symptoms almost immediately.
Wow, thank you both so much for all this information.
I honestly had no idea that I was not supposed to take my medication before a blood test and I have done so before every test I’ve ever had! I will correct that immediately.
I also didn’t know about the ranges only being applicable to the specific lab, thank you for that information.
I will aim to increase my vitamin levels - at the moment I’m only taking an immune support supplement from Together Health (C , Zinc & Selenium) and a cod liver oil + D3 supplement. Plus probiotics (Optibac) and magnesium (Beauty Pie). I can see I need to add in at least B vitamins.
Thank you for the information on gut health and gluten, I will read through the links, I think it’s an issue for me (persistent nausea and abdominal pain).
Thorne Basic B recommended vitamin B complex that contains folate, but they are large capsules. (You can tip powder out if can’t swallow capsule)
Thorne currently difficult to find at reasonable price, should be around £20
If you want to try a different brand in the meantime, one with virtually identical doses of the ingredients, and bioavailable too, then take a look at Vitablossom Liposomal B Complex. Amazon sometimes has it branded Vitablossom but it's also available there branded as Yipmai, it's the same supplement
IMPORTANT......If you are taking vitamin B complex, or any supplements containing biotin, remember to stop these 7 days before ALL BLOOD TESTS , as biotin can falsely affect test results
thank you - I will increase my vitamin D and start taking it with dinner, I didn’t know about taking it away from my levothyroxine (I definitely need more than a well mouse does 😆😂)
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Help with thyroid readings please 
Struggling with symptoms I presume are from Levothyroxine 
Medicheck results 
Having hypo symptoms
Thyroid results 
