Scientists that study the effect of age on thyroid-stimulating hormone (TSH), Free T4 (FT4) and Free T3 (FT3) thyroid hormones often exclude the age group from birth up to age 16, 18, or 19. They usually exclude children and teenagers because they know they are different. Describing their TSH and thyroid hormones is its own … Continue reading Pediatric and teenage TSH, FT4, and FT3 levels
Scientists have been explaining that TSH responds to thyroid hormones differently in childhood, early adulthood, late adulthood and very advanced age. This poses a problem for regions that have implemented TSH-only screening for thyroid dysfunction. The effect of age on TSH is one of many factors that can make this screening test less accurate (Ling … Continue reading Age bias may hide hypothyroidism under a normal TSH
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?
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
A normal ratio of Free T3 (FT3) to Free T4 (FT4) thyroid hormones appears to be a basic principle in thyroid hormone economy when no thyroid hormone dosing and no disease interfere. In this post, I provide graphs, quotations, and discussions from Gullo, Strich, and Anderson as I present their FT3:FT4 ratio results, and I … Continue reading Normal FT3:FT4 thyroid hormone ratios in large populations