Thyroid UK
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Labs say normal?

Hi, new here and a bit confused by the results of a recent lab test.

It said that it was all in the normal range and it was (some were low normal though). I also have been diagnosed with very low cortisol in an adrenal profile that I had done earlier in the year.

I'm just surprised that my numbers would be ok given how low my cortisol levels are. I have some symptoms off an under active thyroid but not all, including weight gain, fatigue, cold extremities, aching muscles and joints, brain fog. In the past I have attributed them (and others) to menopause and sleep apnea, but autoimmune disorders also run in one side of my family, so this seemed like a reasonable thing to look into.

I won't lie and say I always eat well; I don't, but I do try to exercise within the limits of what my exhaustion and pain allow. I'm not pinning all my hopes on a hypothyroid diagnose, but if it that's what it is, it would be great to feel better. It's been a long time.

Any idea where I should go with this next? I am willing to self medicate. Any advice is more than welcome!

4 Replies

greenmug If you post the results of the tests, including the reference ranges, members will be able to comment. It's not really possible to say anything without seeing the results.

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Thanks Seaside Susie - here they are:

TSH - 1.48 ref 0.27 - 4.20

T4 Total - 73.1 ref 64.5 - 142.0

Free T4 - 14.16 ref 12 -22

Free T3 - 4.66 ref 3.1 -6.8

Antiperoxidase abs - 15.3 ref <34

Antithyroglobulin Abs 15 ref <115

B12 - 406 ref 140 - 725

Serum Folate - 45.40 ref 0.83 - 60.8 (It had a < in front but I checked with the lab and they said it is well within the normal range despite that.


greenmug Your TSH is in a pretty good place, what you'd expect in a healthy person. However, your total T4 shows that your thyroid is producing some but not a great amount, your free T4 is low in range (26%) but at this stage you're managing to make a reasonable amount of FT3 considering how low your FT4 is (just less than half way through range at 42%)

[With such a low TSH you'd expect to see a much higher FT4 in a normal healthy person (probably above 50%). ]

As these are all in range you won't get a diagnosis of primary Hypothyroidism. As you have some symptoms of Hypothyroidism, it's possible that you might have secondary Hypothyroidism where the problem lies with the pituitary or hypothalamus and you should ask to be referred to an endocrinologist for this to be investigated.


Your Antibodies are low so don't indicate autoimmune thyroid disease. However, one negative test doesn't rule it out completely, you'd need a few negatives for that.


B12 - 406 ref 140 - 725

Serum Folate - 45.40 ref 0.83 - 60.8

With B12, anything under 500 can cause neurological problems so you might want to supplement with sublingual methylcobalamin lozenges 1000mcg daily to increase that. The recommended level is very top of range, even 900-1000.

Folate is fine, it should be at least half way through it's range.

When taking B12 we also need a B Complex to balance all the B vitamins.


Aching muscles and joints could possibly be linked to low Vit D so that should be tested. Also worth getting ferritin tested (low ferritin can be linked with fatigue).


What was suggested to be done about your low cortisol? Exactly how low was it?

Dr Myhill has an article on understanding adrenal test results

As a general thing, lots of Vit C and a B Complex support adrenals, but depending on how low they are you may need specific supplements. You might want to put your adrenal results in a new post for others to respond, adrenals aren't my strong point.

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Thank you so much SeasideSusie. I regularly take a D3 supplement and the last time I was tested for it I was actually over the amount recommended, so I cut back on it. I will definitely get sublingual methylcobalamin lozenges 1000mcg though, and am already taking a B complex and will also get my ferritin levels checked.

Here are the results of my salivary cortisol test from a few months back:


12.3 / ref 13.0 - 24.0nmol/LCortisol -


1.4 / ref 5.0 - 8.0nmol/LCortisol -


1.5 / ref 4.0 - 7.0nmol/LCortisol -


1.2 / ref 1.0 - 3.0nmol/LCortisol -


2.1 / ref 1.0 - 3.0nmol/LCortisol -

Sum 18.5 / ref 23.0 - 42.0nmol/L

DHEA-S Average 3.5 / ref 2.0 - 10.0ng/m

Cortisol:DHEA-S Ratio 5.3 : 1 / ref 5.0 - 6.0 Ratio

With the exception of the two night readings + the DHEA it's all way under what it needs to be. I have been trying to address it with diet, vitamins and amino acids. I also tried a cortisol replacement, but it made me very ill so I had to stop and am now very wary of anything that is too activating for that reason.

I will also post these results in a new thread to see what if anything others have to say.

Thanks again for your advice.


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