No one wants to be ageist or sexist in thyroid screening or diagnosis. But if we are blind to the way that age and sex can distort the hypothalamus-pituitary-thyroid (HPT) axis, our interpretations of thyroid hormone levels and TSH will inevitably become ageist and sexist by refusing to respect and accommodate human diversity. In a … Continue reading Age, sex and TSH-FT4-FT3 relationships: Advanced lessons
There's a lot of confusion out there about Free T3: Free T4 ratios in bloodstream. Part of the confusion is about how these ratios are expressed in numbers and phrases. Should you express this ratio in blood as 1:4, 4:1 or 0.25, or 4.00? A second confusion may lead to a more substantial and harmful … Continue reading An example of confusion about Free T3: Free T4 ratios
In 2011, Gullo's research team published a landmark study in thyroid therapy titled "Levothyroxine Monotherapy Cannot Guarantee Euthyroidism in All Athyreotic Patients." Gullo and colleagues examined the TSH, FT3 and FT4 levels and the FT3:FT4 ratios of 1,811 thyroidless patients on levothyroxine (LT4) monotherapy and compared them with 3,875 healthy controls. Gullo's study shook the … Continue reading Gullo: LT4 monotherapy and thyroid loss invert FT3 and FT4 per unit of TSH
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
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 be focusing our attention. In these posts, I aim to improve thyroid therapy by debunking … Continue reading Principles and Practical tips for Reverse T3, FT3, FT4
