Can anyone interpret my thyroid function results?

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They’ve come back as ‘normal’ but I wanted to know which end of normal I’m at.

The test was for Serum TSH Level. Result is 1.6mIU/L Range: [0.3 - 4.5] Euthyroid picture.

Thank you in advance

The range is given 0.3-4.5 so you are somewhere in the middle. A normal result

1.6 is a pretty good TSH but what were your free T3 & free t4 levels (assuming they were both tested). Have you had a thyroid problem or are they testing to see if you do have one?

With that result you’re not at either end of normal. Just normal and average.

If you’re having symptoms that make you think all is not right, you can request a more detailed thyroid test where they check other numbers. I can’t remember what though...

I don’t think they tested anything else. They did the test because 2 years ago they found a nodule on the thyroid during a routine scan. They didn’t seem particularly concerned however.... hopefully all ok. Thank you all for your replies

Yeah they should have tested Free T4 and Free T3 as well for a proper picture of how your thyroid is working.

TSH isn't made by the thyroid, its made by the pituitary gland to stimulate the thyroid, but as it seems to be at a normal level, the implication is that it is asking for a certain amount of thyroid hormone and the thyroid is obliging.

Otherwise the TSH would be high as the pituitary starts to shout for more hormone production, and the thyroid is unable to produce it, so the pituitary shouts even louder ie produces more Thyroid Stimulating Hormone! Even if it were between 5 and 10 they'd probably consider it within the realms of normal in treatment terms, even though its out of range, so at your level it looks fine.

GP here. I cannot give specific health advice here, but can give general information.

For a routine thyroid screening test, the TSH would be tested first. The T3/T4 would only be tested if the TSH is abnormal, or if the TSH result is close to the limits AND the patient has significant symptoms.
The result you give is in the middle of the normal range, so I would not expect the T3/T4 to be tested in the normal course of things.

If you have any concerns about this, or are having symptoms you're worried about, you should see your GP.

That seems OK but for TTC, for example it's better to be around 1... for reference before I was medicated my numbers were in the 70s and yes I mean seventys

Thanks everyone - great explanations. I feel reassured

What do you think of this article Fluffy? I’ve been hypothyroid for 20 years and have done a lot of reading about it. Stop The Thyroid Madness and other sources recommend full thyroid panel tests.

I have multiple nodules (last 9 years) and at last blood test my tsh was 2.5. Dr happy with that as I have not symptoms. Last test was 5 years ago. They don’t routinely test unless I become symptomatic.