I was wondering if any more knowledgeable folks had any ideas about what could be going on with my friend's thyroid results? They seem crazy - I don't understand how she can have a reasonably "normal" TSH level with such unbelievably low FT4 and FT3.
She's a 41 year-old female, does not have any thyroid diagnosis and does not take any medications. She is vegan but her vitamin levels were pretty good (folate: 55% through range, B12: 76% through range, vit. D: 48% through range (could be a bit better)), although various iron markers are a bit low. She took the test at 09:00am via a blood draw at a local clinic and sent it off immediately, and was fasted with only water beforehand, and no exercise within 48 hours (we had to cancel our run together the previous day!).
The Medichecks doctor's comments did mention the low iron but said that her thyroid results are (this is a direct quote) "[...] not a cause for concern." I couldn't believe it - no wonder she's been feeling out of sorts and fatigued of late!
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These results are pretty horrible, I would expect her to feel awful.TSH should be much higher when both fT3 and fT4 are low. On the other hand a TSH around 1.5 should stimulate the thyroid to secrete sufficient hormone, this shows her TSH has low bioactivity.
There is no need to fast before a thyroid blood test. Some people believe fasting raises TSH, if this were the case it would be counterproductive for her as a lower TSH would have made her fT3 and fT4 a little lower and got a diagnosis. There's certainly no reason to skip exercising, exercise does increase TSH a little but not enough to make much difference.
A subnormal TSH like this can have many causes including pituitary failure, a previous period of high thyroid hormones, fasting, depression and concurrent illnesses
Is she on a strict diet? What medicines / supplements does she take? Does she have depression or any other illnesses? Has she had a whiplash type injury?
Thank you so much for your (late night) reply, jimh111 much appreciated!
She has no other illnesses, that she's aware of and is generally very fit and healthy - she's actually my running coach... but she has felt increasingly 'not herself' and 'out of sorts' recently and she's trying to get to the bottom of it. She is a very strict vegan and eats very cleanly - only food she prepares herself and is low gluten generally, and completely caffeine free. She has recently started real-time blood glucose monitoring and has found that some berries, such as blueberries, give her a big glucose spike that makes her feel "high" - a sugar rush. I think she feels her athletic performance (running and strength training, mainly) have deteriorated a lot - it's hard for me to say as she's a much better athlete than me! She is not perimenopausal, as far as I know (we do talk about these sorts of things) and she has definitely not had any whiplash type injuries. The only grey area for me is that I don't know exactly what supplements she takes - but I can ask her tomorrow.
She asked for my opinion on her thyroid results as she knows about my recent autoimmune diagnosis... I was shocked to see her T4 and T3 are worse than mine (although her TSH and antibodies are way better than mine)... and HORRFIED that they were described by a doctor as "not a cause for concern" - I'm concerned on her behalf!
Edit: it was a more full blood test than only thyroid (Medichecks Ultimate Performance Blood Test) and no exercise, fasted, etc. were the recommendations for that suite of tests.
It matters how many calories she it getting daily. If she is on a low calorie diet her TSH will be lower than normal (for given fT3, fT4) and her metabolism will slow down. This is how the body protects itself during periods of famine. Being keen on exercise will with determination keep the physical metabolism up but it won't help the effects on all the other factors the thyroid controls.Central hypothyroidism is usually caused by a pituitary problem but usually the TSH is lower and the body tries to preserve fT3. It's more likely the problem is caused by diet or supplements/ medicines.
Thank you, again, for your very valuable wisdom and insights!
I've just got back from a run with my friend and reported back all this information. She did not, at the time of the test, take any supplements or medication at all - she's very against taking any types of medication - so there are no additional confounding factors in terms of supplements/medication outside of diet. I did say she might need to up her calories but she's pretty sure her caloric intake is fairly high - she eats a lot of things like avocados, nuts and seeds. She also has a good broad intake of different vegetables, particularly peas, potatoes, broccoli, spinach, cauliflower, etc. often dressed with olive oil and herbs/spices.
I was wondering about something going on with her pituitary since the TSH level doesn't seem to be responding to the through the floor FT4/FT3 levels.
Possibly pituitary but it will be difficult to get a referral to an endocrinologist and get them to test it thoroughly. She should describe how it affects her daily kife and be assertive.
You've been so helpful! This is pretty much the conclusion we came to between us on our (very rainy) run and chat this morning 😊
She also has a toddler and a demanding job so the main thing is overwhelming fatigue (that she very eloquently described as feeling like she's "permanently pulling a caravan"), which she is going to try to pursue through the BUPA route.
She could have Central Hypothyroidism (CH) but getting a diagnosis for that is very difficult.
In CH the problem could be caused by a malfunctioning pituitary or hypothalamus. The thyroid itself could be perfectly healthy.
The pituitary produces TSH (Thyroid Stimulating Hormone) which stimulates the thyroid to produce all of the body's supply of T4, and about 20% of the body's supply of T3. If the TSH is too low the thyroid won't produce enough T4 and T3.
The hypothalamus produces TRH (Thyrotropin Releasing Hormone - Thyrotropin is another name for TSH) i.e. it stimulates the pituitary to produce TSH. If there isn't enough TRH then there will be too little TSH, and this leads to low levels of T4 and T3.
CH is a blanket term for problems with the pituitary/hypothalamus.
If, after investigation, the actual problem is discovered to be with the pituitary this is known as Secondary Hypothyroidism.
If, after investigation, the actual problem is discovered to be with the hypothalamus this is known as Tertiary Hypothyroidism.
Doctors will use the term CH most of the time, rather than Secondary or Tertiary Hypothyroidism.
Note that doctors (wrongly, in my opinion) think that CH is vanishingly rare so they don't test for it. The other HUGE problem we have is that doctors think that knowing the TSH a patient has is all they need to know. And if the TSH is in range then the patient is healthy. They don't care if the T4 and T3 are really low. (sarcasm on) The TSH, to them, is all that counts because the pituitary is a perfect organ that always functions perfectly, from now to the end of time. Amen. (sarcasm off)
The most common form of hypothyroidism is Primary Hypothyroidism where the problem is with the thyroid.
In each case above the treatment is the same : replacing the missing T4 and, if the patient is lucky, they will get a replacement for the missing T3 too, but that isn't easy to get. In a healthy person T4 is converted into T3 so that most doctors have decided that replacing T3 isn't necessary.
Since the antibody counts are "normal" your friend is unlikely to have autoimmune thyroiditis like Hashimoto's or Ord's. But since antibody levels fluctuate it is possible.
The different types of thyroiditis are mentioned in the above link.
Thank you so much humanbean - really appreciate your helpful insights too!
You are thinking along similar lines to me... maybe part of the "thyroid signalling chain" is a bit askew so her TSH is not going up and her thyroid simply doesn't "know" to replenish her T4/T3 levels. I've warned her that it might be quite a challenge to get to the bottom of everything - she's thinking of trying to get things moving through her work BUPA insurance, so fingers crossed.
Thank you also for the additional links to other possibilities... I've encouraged her to join this forum so she can benefit from everyone's wisdom directly herself 😊
Hi.Because high FT4 is paired with Low FT3, it actually does not look like thyroid disease but something else in the lines of an acute infection in the body. That is because FT4 when high is hyperthyroid and FT3 when low ifla hypothyroid so that's not possible to have both.
The good news is her antibodies are well whitin an optimal range.
Why didn't she had her T3 and T4 tested?
I would recommend a full blood panel with liver enzymes, and definitely looking at folate.
Also, iron plays a vital role for thyroid hormones, so if she is low, she needs to fix that - if vegan, a good clean seaweed might help. If omnivore, liver is the best option - capsules or cooked.
Before considering any seaweed it is important to consider its iodine content.
Optimum ranges for thyroid depend on the lab doing the test! We see FT4 ranges which have almost no overlap at all. And the units used. In the UK we do NOT use ng/DL for Free T4, for one example.
And, while we argue suppressed TSH can be OK, a TSH of zero could very well indicate hyperthyroidism/over-medication. You simply cannot just claim anything less than 2 is optimum.
T4 and T3 (I assume you mean Total tests) are rarely done in the UK. To a considerable extent they are too much an indication of Thyroid Binding Globulin levels.
While liver is potentially very good at providing iron, it is important not to consume too much and take in excess vitamin A.
Many thanks for highlighting the need to think about seaweed's iodine content, helvella ! I can also attest to the fact that she certainly will not be eating liver any time soon - she the most staunch vegan I know... and I know A LOT of vegans. Thank you very much for your cautionary reminders on this topic. 👍
Thanks for your input, DietRehab... it might be a bit hard to see, but the images show the reference ranges that the lab used for their tests - they indicate that her FT4 is, in fact, almost rock bottom (not high)... it's only 7% of the way through the 'normal' range. She didn't get T4 or T3 tested because she didn't know she had a thyroid problem - she did a broad panel of tests in an attempt to pin down what's been causing her increasingly challenging symptoms.
I do agree that it's good news that her thyroid antibodies appear to be OK, at the time of these tests.
In actuality, contrary to popular belief, iodine is crucial for thyroid health - inability to produce T3 or T4 from their precursors is directly linked to Iodine availability, not serum iodine. As iodine can be present, but an impaired thyroid function will render that not bioavailable, hence your serum iodine can be fine and dandy when in actuality is not available for uptake.At least that is what latest research is showing - I can assure you of that as well, as having Hashimoto's and secondary hypothyroidism myself, I take daily iodine and that has helped me tremendously with my symptoms and my test results.
Additionally, labs take their ranges from research papers that are done on people from 18 to 75 considered healthy, with no discrimination between genders (meaning they were never diagnosed officially with a thyroid disorder or any other hormonal imbalance, which does not mean they are healthy). Plus, the optimal ranges I shared are the actual optimal values - the lab ranges are normal values, not optimal values.
Yes, you can argue any number for TSH for example under 2 can have different meanings, which is why you read it in combination with the other tests. And do remember that TSH is not a thyroid hormone, TSH is Thyroid Stimulating Hormone created by the pituitary gland - you can have very low TSH and all thyroid hormones be perfect, which means you might be eating a very low carbohydrate diet and there is nothing wrong with your thyroid.
Lastly, I live in the UK and get my labs through my GP - I have to insists, but I always get my T3 and T4.
Hope you get more actual information before jumping in on a ship of advice. I simply shared knowledge that is not shared by practitioners as unfortunately they do not have the time to research all the latest developments and findings in each medical area.
It can take more than 20 years for latest findings to be shared to and adopted by the medical community as a new standard.
Being a vegan it would be an idea for them to get an iodine test done. I know from personal experience and being on a plant based diet that my FT4 was bottom of the range for many years and more recently below range.
When I got a non loading iodine test done I was found to be very deficient. Even so when I eventually got to see an endo they told me not to supplement as it would confuse my situation. You do need to be properly guided if iodine is supplemented as it can make hypothyroidism worse. I decided to wait and see if I would be prescribed thyroid hormones after thyroidectomy.
I was very symptomatic for many years and I still don't have a diagnosis of hypothyroidism; I was prescribed levothyroxine post partial thyroidectomy due to tiredness. At some point I will do another iodine test to see how much my levels have improved with now taking levo for almost a year. Even testing of iodine is a controversial subject some methods are said to be more reliable than others)
When iodine is mentioned on the forum it is a very emotive subject; it always results in interesting replies. Even testing of iodine is a controversial subject some methods are said to be more reliable than others.
Obviously I'm not saying your friend is deficient but it could be a possibility. As others have mentioned Central hypothyroidism is another possibility.
There is a pinned post by tattybogle that has lots of links to previous posts discussing iodine. Sorry not able to link to it as don't know how 🤔
This is really great, Hedgeree - thank you very much!
Your insight as a plant-based person yourself is extremely valuable. I mentioned iodine to her - but with a very heavy caveat to **be careful** if she considers looking at iodine levels as I'm aware that it could cause as much harm as good.
As I mentioned to humanbean above, I've encouraged her to join this forum so she can start to research for herself and maybe reach out to others with similar experiences. Thank you again 😊
I was a bit wary of mentioning iodine but with them being a vegan thought it was important. The focus is usually on B12 levels and how to maintain them when you eat a plant based diet.
Unfortunately I didn't even consider iodine being an issue until I started exploring my symptoms and having an iodine test.
Also getting online access to my patient record and discovering that I had a low in range FT4 and had for many years was quite an eye-opener.
Click on "Read the list of available tests" and on page 3 of the pdf you'll see
Urine Iodine Test:
Specimen requirements: Urine
Cost: £76
Order Code: END25
Turnaround time: 5 - 10 days
Iodine is an essential trace element, vital for healthy thyroid function. Adequate levels are required to enable the production of T3 and T4 thyroid hormones, whilst also being required in other areas of health.
Deficiencies can lead to impaired heat and energy production, mental function and slow metabolism. Urine iodine is one of the best measures of iodine status. This test is not performed as a loading test, but can be used to establish existing levels or to monitor iodine supplementation.
Content on HealthUnlocked does not replace the relationship between you and doctors or other healthcare professionals nor the advice you receive from them.
Never delay seeking advice or dialling emergency services because of something that you have read on HealthUnlocked.
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