72. Garber JR, Cobin RH, Gharib H, Hennessey JV, Klein I, Mechanick JI, et al. American Association of Clinical Endocrinologists and American Thyroid Association Taskforce on Hypothyroidism in Adults. Clinical practice guidelines for hypothyroidism in adults: co-sponsored by the American Association of Clinical Endocrinologists and the American Thyroid Association. Thyroid. 2012;22:1200–1235. [PMID: 22954017] [PubMed]
55. National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III) Third Report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III) final report. Circulation. 2002;106:3143–3421. [PMID: 12485966] [PubMed]
The main job of the thyroid gland is to combine the salt iodine with the amino acid tyrosine to make thyroid hormone. Whenever the thyroid gland has a hard time making enough thyroid hormone, it becomes stressed and grows bigger to try to do its job better, forming a “goiter” (enlarged thyroid). Substances that interfere with normal thyroid function are called “goitrogens” because they have the potential to cause goiter.
l-Thyroxine monotherapy, the novel and physiologically savvy method for treatment of hypothyroidism, contrasted with the traditional approach of natural thyroid preparations that was marred by potency concerns. In less than a decade, there was a major shift in treatment of hypothyroidism such that normalization of TSH with l-thyroxine monotherapy became the new standard of care (Appendix Table) (52). Many clinicians advocated for this to be first-line therapy and for patients previously treated with desiccated thyroid to be transitioned to l-thyroxine monotherapy (50).
Cases of myxedema were reported in the mid–19th century but were not initially connected with a deficiency from the thyroid gland until surgeons identified incident myxedema after thyroidectomy (11). Initial treatment strategies were largely insufficient and primarily symptom directed, including hot baths and institutionalization (12). The significant morbidity and mortality in the absence of efficacious treatment were clear, and thus the need to “replace” the thyroid through surgical transplantation or oral or intravenous routes was established. Thyroid transplant had some early successes, but for many patients symptoms recurred and the procedure even had to be repeated (13). Because of the rapidity and transiency of improvement (12), it was hypothesized that symptoms improved by absorption of the “juice” of the donor gland (14).
l-Thyroxine monotherapy for athyreotic rats results in a high T4:T3 ratio at doses sufficient to normalize serum TSH levels (8). Yet, the brain, liver, and skeletal muscle tissues of these l-thyroxine–treated animals continue to exhibit markers of hypothyroidism (9), probably because of the inability of l-thyroxine monotherapy to restore tissue levels of T3 (8). This is probably a direct consequence of lower serum T3 levels and the relatively high T4 concentration in these tissues, which inactivates the type 2 iodothyronine deiodinase (D2). In the hypothalamus, loss of D2 is minimal in the presence of T4, which increases sensitivity to T4 levels and explains TSH normalization, despite relatively lower levels of serum T3. Only combination therapy with l-thyroxine plus l-triiodothyronine normalized all thyroid hormone–dependent measures (9), including serum and tissue T3 levels (8). Whether tissue-specific markers of hypothyroidism are restored with l-thyroxine monotherapy in humans remains to be determined, as does the ability of l-thyroxine plus l-triiodothyronine combination therapy to normalize the serum T4:T3 ratio without adverse events. The development of a novel drug delivery system for l-triiodothyronine would facilitate these studies (5).
You may have read that green, leafy veggies like kale, bok choy, broccoli, and Brussels sprouts can make hypothyroidism worse. But before you keep reading, ask yourself a question: Do you live in the United States? That’s key — because if you do, you likely don’t need to worry about these cancer-fighting veggies messing with your hypothyroidism management. (7)
Affiliate Disclosure: There are links on this site that can be defined as affiliate links. This means that I may receive a small commission (at no cost to you) if you purchase something when clicking on the links that take you through to a different website. By clicking on the links, you are in no way obligated to buy.
Please Note: The material on this site is provided for informational purposes only and is not medical advice. Always consult your physician before beginning any diet or exercise program.
Copyright © livehopelupus.org