Does the statistically-defined “normal” TSH reference range for the healthy population describe the TSH range for a healthy individual? Does having a TSH within the normal laboratory range always mean you, as an individual are biologically euthyroid? Does falling outside… Read More ›
This post follows up on several recent posts on the topic of Reverse T3 (RT3) and our thyroid hormone conversion enzymes, the three deiodinases. Here I’m providing some practical tips about Reverse T3 testing, test interpretation, and where we should… Read More ›
We’ve known since at least 2002 that being within “normal range” is never good enough when it comes to thyroid hormone blood tests. An important set of articles has taught us that each human being has an optimal range for… Read More ›
Recently I came across the information about the Free T3 lab test assay kit recall by Abbott Laboratories announced in late 2018. The recall was initiated in October 2018 and the FDA record was published in February 2019. The reason… Read More ›
Table 17.1 in Braverman & Cooper’s 2013 chapter in Werner & Ingbar’s The Thyroid textbook, 10th edition, lists many causes of thyrotoxicosis. The only time the TSH _hormone_ is listed as a cause of thyrotoxicosis is in the case of… Read More ›
Many substances and health factors can, independently of thyroid hormones, lower TSH secretion significantly. These factors are not listed in Braverman & Cooper’s chapter on thyrotoxicosis in Werner & Ingbar’s The Thyroid textbook, 10th edition 2013, because their chapter avoids… Read More ›
In late 2018, in Ontario, Life Labs changed its reference range for Free T3 (Triiodothyronine) thyroid lab tests. In our closed Canadian Thyroid Support Group where patients share their lab results and therapy progress over time, this particular Free T3… Read More ›
Hypothyroidism is a thyroid hormone insufficiency, so it’s only logical to measure the success of therapy by the goal: T4 and T3 thyroid hormone sufficiency. Especially T3 sufficiency, the active hormone. Lab tests like Free T3 and Free T4 can… Read More ›