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… Read More ›
FT3:FT4 ratio
Gullo: LT4 monotherapy and thyroid loss invert FT3 and FT4 per unit of TSH
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… Read More ›
Normal FT3:FT4 thyroid hormone ratios in large populations
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. When measured in pmol/L, the ratio is consistent… Read More ›
Principles and Practical tips for Reverse T3, FT3, FT4
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 ›
The TSH-T3 disjoint in thyroid therapy
There’s a deep lie behind today’s TSH-based definition of “euthyroid” status and today’s policies of TSH normalization in therapy. The lie is that the loss of the thyroid and the initiation of thyroid hormone dosing has NOT altered and skewed… Read More ›
Stop spreading the unscientific myth about the normal T4:T3 ratio!
Sigh. Just sigh. Even some of our best thyroid patient advocates can unknowingly share misinformation about thyroid therapy. Mary Shomon’s thyroid articles on Verywell.com are usually to be trusted. But yesterday I was saddened to see that an article supposedly… Read More ›
Analyze thyroid lab results using SPINA-Thyr
This post walks through the process of using the SPINA-Thyr to interpret thyroid lab test results. OVERVIEW SPINA-Thyr is a free diagnostic application developed by research endocrinologists who use it in peer-reviewed medical research. SPINA-Thyr takes thyroid laboratory test values TSH,… Read More ›
Low-normal FT3 increases Alzheimer’s Disease risk
SOURCE Quinlan, P., Horvath, A., Wallin, A., & Svensson, J. (2019). Low serum concentration of free triiodothyronine (FT3) is associated with increased risk of Alzheimer’s disease. Psychoneuroendocrinology, 99, 112–119. https://doi.org/10.1016/j.psyneuen.2018.09.002 JAN 2019: Study reports increased risk of Alzheimer’s disease with… Read More ›