The image above is from the article “Mechanisms of action of thyroid hormones”, available for free at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3433956/.
Learn more about this extremely important gland, fundamental to life, here:
If you use (or know someone who uses) Levoid, Synthroid, Puran, Euthyrox and the like, read it (or show it to someone who does):
1️⃣ These are all trade names for levothyroxine sodium, whose only function in the body is basically the same as that of T4 (thyroxine): to be transformed into T3 (triiodothyronine). T4 itself has no recognized biological function: inside the cells, T4 has to be transformed into T3, which is the hormone that actually stimulates metabolism (find out more at https://icaro.med.br/T3/).
2️⃣ The problem is that for T4 to turn into T3, you need several conditions at the same time: sufficient quantity and quality of lifestyle habits (https://icaro.med.br/15habitos/), vitamins (mainly D and B-complex), minerals (especially iron, selenium and zinc) and other hormones (such as progesterone, testosterone and low levels of leptin). In other words, many people are “taking T4” (ingesting any of the drugs I mentioned above) and still have symptoms of hypothyroidism (https://icaro.med.br/hipotireoidismo/), because T4 that isn't converted into T3 is practically “useless”.
3️⃣ Even with the above conditions, in rare cases the patient can still produce T3, but face problems with the receptors for it. Just as each lock is opened by a specific key, each hormone has its own specific receptor. A hormone without free, quality receptors to receive it cannot act properly.
4️⃣ The excess T4 administered can still be converted into reverse T3, which is inactive and can “clog” the receptors, impairing the action of active T3.
5️⃣ T3 is so important that the thyroid produces around 15% of it, while the rest is T4. Therefore, those who no longer have a thyroid need to pay even more attention to the amount of circulating T3!
6️⃣ I see patients with “thyroid problems” almost every day, many of whom are poorly assessed and treated, unfortunately.
Got it? If not, go to the links above and study. The videos and texts will help you!
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