Can a normal TSH rule out thyroid disease?

If you are well-informed by current thyroid science, you already know the answer to the question in the title. "No. A normal TSH cannot rule out thyroid disease." Since the 1990s, physicians have been taught to use simplistic category-based interpretations of TSH (and Free T4) as "in or out of range" to classify people as … Continue reading Can a normal TSH rule out thyroid disease?

What’s wrong with calling TSH, FT3 and FT4 “thyroid function tests”?

A Google search for "thyroid function tests" brought up a definition square at the top of the search results. It says that "Thyroid function tests" is a collective term for blood tests used to check the function of the thyroid. A TFT panel typically includes thyroid-stimulating hormone (TSH, thyrotropin) and thyroxine (T4), and triiodothyronine (T3) depending on local laboratory policy." (Thyroid Function … Continue reading What’s wrong with calling TSH, FT3 and FT4 “thyroid function tests”?

Are normal thyroid reference ranges risk-free zones?

Commonly, when scanning laboratory results, a physician will look for values that are “out of range” (high or low). It is often presumed that if FT4, TSH, and FT3 are all "in the normal range," those hormone levels won't be a problem for the heart, the liver, the kidney, the brain, and so on. It … Continue reading Are normal thyroid reference ranges risk-free zones?

Reference list for analyzing normal thyroid lab results

This list provides all references in alphabetical order for the following series of posts: Series introduction: Cognitive barriers to analyzing "normal" thyroid lab resultsBarrier 1: Are normal thyroid reference ranges risk-free zones?Barrier 2: What's wrong with calling TSH, FT3 and FT4 "thyroid function tests"?Barrier 3: Can a normal TSH rule out thyroid disease? 3.1: Age … Continue reading Reference list for analyzing normal thyroid lab results

Cognitive barriers to analyzing “normal” thyroid lab results

Here is a common moment that occurs now and then in doctor’s offices. The physician looks up from their computer screen and tells the patient, “Your thyroid function tests came back normal, so nothing is wrong with your thyroid.” That statement reveals the dismal state of medical ignorance about normal-range thyroid lab results. It’s not … Continue reading Cognitive barriers to analyzing “normal” thyroid lab results