The standard guidelines for thyroid testing state first you must test thyroid stimulating hormone (TSH), then if TSH is out of the ‘NORMAL’ reference range go ahead and assess free thyroxine (T4). But is this enough? This article lists the top 5 thyroid tests that will help you find out what’s really going on.
How Effective is The Single TSH Test?
It’s true, TSH is an important messenger hormone. But did you know this hormone is not actually produced by the thyroid?
TSH is made in the pituitary which is an endocrine gland about the size of a pea that’s located deep within the brain.
When the pituitary releases TSH this hormone travels to the thyroid via the bloodstream to stimulate production of the thyroid hormones. The thyroid responds by getting busy making important thyroid hormones such as T4 and triiodothyronine (T3).
As you would expect, more TSH is released when the body needs to step up production of your thyroid hormones. For this reason, a high TSH result indicates a hypothyroid disorder.
The ‘Test TSH First’ Strategy
You may be told no further investigation is necessary when your TSH result falls within the standard reference range. Even when you have symptoms that strongly suggest your thyroid is functioning well below par.
The Single TSH Test Is Not Enough
The problem is, the single TSH test is not a reliable indicator of thyroid function. It’s the reason a ‘normal’ result can be so misleading.
If you suspect you have a thyroid problem it’s vital to discuss your concerns with a thyroid-literate doctor. Ideally you will get a complete thyroid panel done, and other important diagnostic tests.
- A complete thyroid panel tests TSH along with free T4 (FT4), free T3 (FT3), reverse T3 (RT3), and thyroid antibodies.
- Testing free T4 and T3 can tell you how much of these thyroid hormones are ‘free’ and available to the body. It also tells you how much T4 is converting to the more potent T3.
- Low T3 can indicate under-conversion of T4 to T3. T3 acts on almost every cell and organ in the body. So as a consequence, low T3 leads to a range of hypothyroid symptoms.
WHY Test ‘Reverse T3’ (What Does This Tell You)?
Yes, if you have been under enormous stress, or have been feeling unwell for some time you should check reverse T3. In fact, I believe the reverse T3 blood test is essential to effectively diagnose, and manage a thyroid disorder.
Too much reverse T3 triggers many of the common symptoms associated with a sluggish thyroid. It’s important to know that only a specific test for reverse T3 can identify high levels in the blood. High reverse T3 is associated with long term stress, chronic illness, yo-yo dieting, or a chronic iron deficiency.
How To Check If Your Thyroid Is Under Autoimmune Attack
The #1 reason to test thyroid antibodies is that levels accurately reflect the degree of autoimmune stress within the thyroid. An autoimmune thyroid disorder creates inflammation which can lead to destruction, and loss of function of the thyroid.
The Top 5 Thyroid Tests You Need To Know About
In summary, the top 5 thyroid tests includes:
- Thyroid stimulating hormone (TSH)
- free T4 (FT4)
- free T3 (FT3)
- thyroid antibodies: thyroid peroxidase Abs (TPO Ab) + antithyroglobulin Abs (ATG Ab)
- reverse T3 (RT3)
Proper thyroid testing provides answers, and can assist in diagnosing a specific thyroid disorder. You may find it handy to take along this list when you visit your doctor.
Understanding Thyroid Test Results
Proper interpretation of thyroid function tests requires an understanding of thyroid physiology so it’s important to discuss your results with a doctor who undertands thyroid problems. To get a reliable diagnosis a thyroid-literate doctor will also take a full medical history, discuss your symptoms, and perform a physical examination of your neck.
In the USA and finding it hard to get the thyroid tests you want?
In Australia and finding it hard to get the thyroid tests you want?
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