January 21, 2016

Thyroid part 4 of 5

Articles by Dr. Erdman are for informational purposes, and are not to be taken as specific medical advice.

Now that we’ve covered the anatomy of the thyroid, the possible disruptors of thyroid function and the multitude of symptoms a dysfunctional thyroid can produce in the past three articles, we are now ready to review the testing necessary to diagnose a low functioning thyroid.

The traditional diagnosis of thyroid function is done by assessing how much thyroid stimulating hormone (TSH) the pituitary gland produces. This is kind of an indirect measure of thyroid function. Normal levels should be between 1.0 – 1.5 milli-international units per milliliter. As the name thyroid stimulating hormone suggests, the pituitary gland produces more TSH in response to low thyroid function. This action stimulates the thyroid to produce more thyroid hormone. Hence the higher the TSH production, the more likely you are to have hypothyroidism. However, while this is the primary test, it simply may not be adequate enough in many cases.


It is well known that many patients where the TSH levels fall within the normal ranges, still exhibit signs and symptoms of low thyroid. The TSH test frequently misrepresents the relationship between the pituitary and the thyroid. Part of the problem is that the TSH test fails to account for endocrine disrupting chemicals, which affect many endocrine functions, not just the thyroid. Because some chemicals disrupt other hormones along the signaling system, it can be difficult to identify an imbalance with the TSH test alone.

To see a better picture of your thyroid health, the following lab tests can also be assessed:

Free T3 and T4: these are the actual thyroid hormones. T3 has three iodine molecules attached, and T4 has four. T3 is the biologically active form used by the body. Normal T4 is between 0.9 ng/dL, and T3 is between 240 -450 pg/dL.

Thyroid antibody testing is done by performing two tests, the thyroid peroxidase and antithyroglobulin antibody tests. These two measures will tell you whether you have an autoimmune problem, which means your immune system is attacking its own thyroid. Most doctors rarely give this test a thought. But it is important to rule out this mode of dysfunction.

Use basal body temperatures as another form of testing. If your morning body temperature is below 97.6* F on a regular basis, this is a positive sign of low thyroid function.

In cases where TSH is normal, yet symptoms persist, a thyrotropin releasing hormone (TRH) stimulation test may be performed. This test involves getting a shot of thyrotropin (produced by the hypothalamus gland), which causes the pituitary gland to empty itself of all its stored TSH into the blood stream. Depending on how high these levels rise to can mean a dysfunctional pituitary gland.

A reverse T3 (RT3) test can be performed when chemical toxicity is suspected. Reverse T3 is metabolically inactive and elevated levels indicate heavy metal toxicity is affecting the thyroid function. High stress can also cause RT3 to be elevated, as can adrenal fatigue, low iron stores (ferritin) and acute or chronic illness.

 As you can see, diagnosing thyroid conditions is complex. I am no expert in this field, and if I needed help with a problem like this, I would seek out a natural minded holistic endocrinologist. In our area, I have no idea if one even exists. I have patients that travel to the Altoona area for this type of holistic treatment from medical personnel.


In the next and final article on the thyroid, we will look at the treatments available to those with low thyroid function.