T3 Blood Test

Triiodothyronine (T3) is made by the thyroid and uses Selenium, Zinc and Iodine to do so.
T3 is also made by the liver by converting T4.

TSH from the Pituitary Gland causes the thyroid gland to make two hormones: triiodothyronine (T3) and thyroxine (T4).

Testing the blood for T3 levels is a good indicator if the thyroid is working correctly or not, however if there is a deficiency of Selenium, Zinc and Iodine, a low level of T3 may not be an indicator of a thyroid not working, but more an indicator of the deficiency. This is why it is important to also test for other indicators.

eg A normal level of T4 combined with a low T3 may not be an indicator of problem thyroid function, because if the thyroid can’t convert the T4 to T3, due to a mineral deficiency, then the problem is the deficiency, not the thyroid.

Synthetic thyroxin such as Synthoid is T4, so if you are taking it, the T4 levels may show as correct even with low T3.

Natural forms of desiccated thyroxin will normally contain a mix of both T4 and some T3.

Typically your GP will ask for TSH test on your blood sample.

The TSH alone will not generally be a good indicator, a full suite of tests normally needs to be done.

TSH, FT4, FT3, TT4, FTI, Resin T3 Uptake, Reverse T3, TPO and TGB Antibodies.

Free (T3) triiodothyronine

Reverse T3

Free (T4) thyroxine

TSH – thyroid-stimulating hormone

TSH is produced when the hypothalamus releases thyrotropin-releasing hormone (TRH). TRH then triggers the pituitary gland to release TSH. TSH causes the thyroid gland to make two hormones: triiodothyronine (T3) and thyroxine (T4).

Thyroid antibodies. TPO

Thyroid Peroxidase Antibodies (TPOAb)
Thyroglobulin Antibodies (TgAb)

This is because it is possible to have normal T4 and TSH levels yet still have low T3 if the body is not converting T4 to T3 sufficiently.

In addition other tests can provide more indicators,

for instance, having been diagnosed with a lump in the thyroid, as shown by ultrasound scan, and with having a fine needle biopsy being inconclusive, my specialist ordered the following:

PTH Parathyroid hormone

TFT Thyroid Function Test

CMP Cmprehensive Metabolic panel

FBE Full blood examination

Thy ABS – thyroid antibodies TPO

Vitamin D

CLE

COMP

A complete test might consist of the following:

Complete Metabolic Panel, not a basic metabolic panel. You have a thyroid disorder and you need as much information as POSSIBLE!

A complete thyroid panel which needs to include TSH, Free T3, Free T4, Total T4, Free Thyroxine Index, Resin T3 Uptake, TPO and TGB antibodies, TBG and Reverse T3.
You NEED to know as much about your thyroid gland as possible and ALL of these blood tests will tell you.

A complete lipid panel and a CBC with auto differential which breaks down the white and red blood cells.

Testing for gluten reactivity, gut function, cross-‐ reactive foods and other parts of your body that your immune system could be attacking.

An ASI (Adrenal Stress Index) which checks your adrenal glands. Your adrenal glands are your “stress glands.”

A 2105 stool microbial test looking to see if you have parasites or h-‐pylori or fungi or mold in your gut.

An Organic acid test which tests for carbohydrate metabolism, fatty acid metabolism, energy production markers, and detoxification markers to name a few.

……..Thyroid Problems

T3 – Triiodothyronine

Blood Tests for Thyroid Disfunction