Goitrogens are substances (whether in drugs, chemicals, or foods) that disrupt the production of thyroid hormones by interfering with iodine uptake in the thyroid gland. This triggers the pituitary to release TSH, which then promotes the growth of thyroid tissue, eventually leading to goiter.
Goitrogenic drugs and chemicals
Chemicals that have been shown to have goitrogenic effects include:
- Sulfadimethoxine, propylthiouracil, potassium perchlorate, and iopanoic acid.
- Some oxazolidines such as goitrin.
- Ions such as thiocyanate (from cigarette smoking for example) and perchlorate decrease iodide uptake by competitive inhibition and, as a consequence of reduced thyroxine and triiodothyronine secretion by the gland, cause, at low doses, an increased release of thyrotropin (by reduced negative feedback), which then stimulates the gland.
- Amiodarone inhibits peripheral conversion of thyroxine to triiodothyronine; also interferes with thyroid hormone action.
- Lithium inhibits thyroid hormone release.
- Phenobarbitone, phenytoin, carbamazepine, rifampin induce metabolic degradation of triiodothyronine (T3) and thyroxine (T4).
- Cassava, when crushed and not detoxified by soaking
- Soybeans (and soybean products such as tofu, soybean oil, soy flour, soy lecithin)
- Pine nuts
- Flax seed, flax seed contains cyanide which transforms into thiocyanate inside the body leading to hypothyroid syndrome.
- Bamboo shoots
- Sweet potatoes
- Vegetables in the genus Brassica[page needed], and other cruciferous vegetables
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- Erdogan MF (2003). "Thiocyanate overload and thyroid disease". BioFactors (Oxford, England) (Review) 19 (3-4): 107–11. doi:10.1002/biof.5520190302. PMID 14757960.
- Mitchell, Richard Sheppard; Kumar, Vinay; Abbas, Abul K.; Fausto, Nelson. Robbins Basic Pathology. Philadelphia: Saunders. ISBN 1-4160-2973-7. 8th edition.