Thyroid UK
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T4 and TSH levels

Hello I am new, and don’t understand my levels, the doctor said my thyroid is slightly under active, but not going to do anything and to have another test in 6 months, I have been suffering with a few symptoms of an under active thyroid, but I thought it was my B12 levels as symptoms are the same and I’ve had low B12 before, My T4 level is 12.9 but not put a range, and my TSH is 5.78 in range (0.35-5.5). But I do not understand it, please help. X

Also my Folate is 5.7 and ferritin is 44.9, B12 350ng/l

7 Replies

TSH of 5.78 is undoubtably HYPOTHYROID and your T4 is near bottom of the range

Thyroid antibodies should have been tested





Must also be tested

Do not wait 6 months the sooner your treated the better otherwise it takes a long time to get better


Folate is 5.7 and ferritin is 44.9, B12 350ng/l


Thank you for quick response


Ferritin, folate,b12,vitd3

All need to be at least halway in their ranges for levithyroxine to be converted to T3 which every cell needs in order to function

Your results on the normal ranges i know of are too low

Its vital to get the actual ranges too


Ask for thyroid antibodies and vitamin D to be tested

For full Thyroid evaluation you need TSH, FT4, TT4, FT3 plus TPO and TG thyroid antibodies. Plus vitamin D, folate, ferritin and B12.

Essential to test thyroid antibodies, FT3 plus vitamins

B12, folate and ferritin are all on low side. Likely vitamin D is too

Private tests are available. NHS often refuses to test FT3 or thyroid antibodies if TSH is in range

Actually your a TSH is above range, so see GZp and ask that they are tested

Always get actual results and ranges on all tests. You are legally entitled to them

Medichecks Thyroid plus ultra vitamin or Blue Horizon Thyroid plus eleven are the most popular choice. DIY finger prick test or option to pay extra for private blood draw. Both companies often have money off offers.

All thyroid tests should ideally be done as early as possible in morning and fasting. This gives highest TSH and most consistent results. (Patient to patient tip, GP will be unaware)

If antibodies are high this is Hashimoto's, (also known by medics here in UK more commonly as autoimmune thyroid disease). About 90% of all primary hypothyroidism in Uk is due to Hashimoto's

Link about thyroid blood tests

Link about antibodies and Hashimoto's

List of hypothyroid symptoms


Hi I understand the T4 range is 11-24 (if I am wrong I am sure someone will correct me) so yours is low. Mine was 11.7. I have some symptoms of hypor but the doctor said it is only borderline and recommended another test in 3 months. x


Yes that’s what my doctor said to me but 6 months x


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