This article is for people interested in getting an overview of the influence of thyroid hormones on bone health at the molecular level. It outlines the way bone transports, metabolizes, and uses thyroid hormones T3 and T4. It also raises theoretical implications for people with low T3 during TSH-suppressive T4 monotherapy. Here I draw mainly on the molecular endocrinologists Bassett and Williams’ 2018 chapter, and I supplement it with additional cited sources. ACTION IN BONE CELLS Osteoblasts are cells responsible for bone formation. They are directly stimulated by T3 hormone. The osteoblasts express both thyroid hormone conversion enzymes found in …
Month: July 2019
The Abbott Free T3 test kit recall of 2018-2019
Recently I came across the information about the Free T3 lab test assay kit recall by Abbott Laboratories announced in late 2018. The recall was initiated in October 2018 and the FDA record was published in February 2019. The reason they list is the potential for a mistakenly lower Free T3 test result. “Samples tested using ARCHITECT Free T3 or ARCHITECT Total T3 assays may show depressed results due to a reagent carryover when testing on board with specific assays on the ARCHITECT i1000SR and i2000/i2999SR platforms.” In other words, the assay kits cause errors when they are processed using …
As of 2019, still no proof that low TSH causes harm to bones
Many research studies have shown a strong association between low TSH and low bone mineral density or osteoporosis. As a result, many guidelines strongly caution against the risk associated with low TSH. Some doctors and thyroid patients have jumped to the conclusion that a low TSH “causes” osteoporosis. Some even believe a low TSH must be avoided at all costs during thyroid therapy, even if lowering their thyroid hormone dose causes chronic hypothyroid symptoms in a patient! But as of 2019, has science proven that lack of TSH “causes” harm to bones? Surprisingly, the answer is NO! Correlation is not …
Overlooked: Hypothyroidism causes osteosclerosis
We should all know that thyrotoxicosis in bone, caused by too much T3 binding to receptors in cells, leads to osteoporosis. (Bassett et al, 2007; Gogakos et al, 2010) Hypothyroidism in bone, characterized by low T3 in bone, is not good for bone, either. (Bassett et al, 2008) Hypothyroidism results in a different bone disorder you rarely hear of: osteoSCLERosis. (Williams, 2013; Bhatnagar et al, 2017). After the prefix “osteo” meaning bone, the word “sclerosis” means abnormal hardening. How many studies and clinical cautions focus on this problem of local T3 deficiency in bone leading to sclerosis? Few. It’s such …
2014 ATA therapy guidelines: 5. Research
This post continues my series of paraphrases of Jonklaas et al’s 2014 guidelines that I left unfinished weeks ago. Posts in this series: 2014 ATA Thyroid therapy guidelines: 1. Levothyroxine 2014 ATA Thyroid therapy guidelines: 2. Ethics 2014 ATA Therapy guidelines: 3. Desiccated thyroid 2014 ATA Therapy guidelines: 4. Using Synthetic T3 2014 ATA therapy guidelines: 5. Research [this post] 6. [ not yet published; still in draft form] 7. [ not yet published; still in draft form] Here I provide paraphrases and quotations of what they set forth for the “ethics” of research in thyroid therapy in Section 18, …