
The free SPINA-Thyr app, developed by research endocrinologist Johannes Dietrich, analyzes TSH, FT3 and FT4 relationships when you are not dosing any T3 hormone. This post provides a walkthrough showing how to use the analysis app.

Learn how to discover your optimal Free T3 and Free T4. Avoid underdose or overdose on any ratio of T4-T3 synthetic or NDT / DTE (desiccated thyroid) therapy.

Learn about the fluctuations in Free T3 levels (and TSH and FT4) outside of thyroid therapy and within T3-T4 combination therapies and T3 monotherapy. Learn how the TSH responds.
Learn why it’s best to take your lab test 12+ hours after your most recent T3 / desiccated thyroid dose.

It’s a common myth that 80% of our daily T3 supply comes from T4-T3 conversion and 20% from the thyroid gland. An analysis of the scientific article that originated this 80/20 myth shows something different: a wide range of metabolic flexibility. What are the implications for thyroid therapy?

Many thyroid patients struggle with a TSH that falls low during therapy, or that fails to elevate when underdosed. Learn how to avoid various health factors that can artificially lower your TSH. Take your lab test when your TSH is highest. Free your TSH to rise naturally — without underdosing yourself.

When you replace some synthetic T4 (Synthroid, Eltroxin) with LT3 (Cytomel), the 4:1 dose equivalency advertised in many product monographs is incorrect. This error causes underdose in some people. Part 1 gives data on LT3 dosing vs LT4 dosing in thyroid science before 1985. Part 2 discusses more recent research.