In the interest of treating people from the root cause of disease, having a complete assessment is critical. When I ask if my patients have had their thyroid tested, they usually don’t entirely know what that entails. This list will help you understand the ins and outs of a FULL thyroid panel!
TSH – Thyroid Stimulating Hormone (TSH) is probably the most commonly tested thyroid hormone. Doctors will run this as part of an annual panel for patients or if a patient presents with symptoms that suggest they may be suffering from dysfunctional thyroid. TSH is the hormone released from the pituitary to tell the thyroid gland to release thyroid hormones. When the gland doesn’t make and release enough thyroid hormones, TSH goes up. When it makes too much – TSH goes down. While this test does help screen for thyroid conditions, it doesn’t give enough information to make a complete diagnosis. Naturopathic doctors also tend to have a much more narrow healthy range for this lab test. Personally, I like to see TSH below 2.2-2.5 and above 0.3. This is much lower than the normal range which goes from 0.3 all the way up 4.0 and even higher with some labs. Unfortunately, this broad reference range contributes to patients being dismissed or misdiagnosed.
Free T3 and T4 – These are your thyroid hormones. They are released from the thyroid gland in response to TSH. In hypothyroidism, not enough T3 and T4 is produced (resulting in elevated TSH). In hyperthyroidism, too much is released (resulting in decreased TSH). The first thyroid hormone created is T4. Then T4 has to be converted to T3 – the more active thyroid hormone. Checking free T3 and T4 can help determine if there is a conversion problem contributing to your symptoms.
Reverse T3 – When stress (and therefore cortisol) levels go up, T4 can be shunted towards reverse T3 instead of T3. Reverse T3 isn’t an active hormone – which is why some people feel so crummy when they are stressed despite having a “normal” TSH. In these cases, free T4 may be normal but free T3 (the stronger thyroid hormone) is below the range for optimal health.
Anti-Thyroperoxidase and Anti-Thyroglobulin – Some people have autoimmune thyroid diseases (Grave’s Disease, Hashimoto’s Thyroiditis). We test for antibodies for thyroperoxidase and thyroglobulin to differentiate autoimmune thyroid disease from non-autoimmune. Presence of these antibodies indicate that the body’s immune system is attacking the thyroid gland. Autoimmune thyroid conditions tend to be much more difficult to treat and can be the reason behind why you are having so many ups and downs since starting your treatment.
Iodine, Iron, Vitamin D3, Selenium, Chromium, Copper, Zinc – Nutrient deficiencies can disrupt thyroid hormone conversion from T4 to T3. These tests can be added as needed, to ensure nutritional adequacy or to highlight a need for supplementation. Fortunately, these are usually easy fixes once they have been identified as part of the problem.
– Excess cortisol can also disrupt conversion of T4 to T3. For cases where a person is particularly stressed, assessing their adrenal function can make a huge difference in the effectiveness of your treatment plan.