Table 1.
The role of nutritional antioxidants in thyroid function.
| Nutritional antioxidant | Role in thyroid function | Reference |
|---|---|---|
| Iodine | Essential for the synthesis of thyroid hormones Antioxidant Antiproliferative agent |
171) |
| Zinc | Required for the activity of enzyme 1,5′-deiodinase which catalyzes the conversion of T4 to T3 Regulator of TRH and TSH synthesis |
(177, 178) |
| Selenium | Constituent of selenoproteins Cofactor of Gpx, deiodinases and thioredoxin reductases |
(181–183) |
| Resveratrol | Mediates the levels of TSH and iodide uptake in thyrocytes by decreasing sodium/iodide symporter expression | (184) |
| Berberine | Decreases the abundance of pathogenic bacteria in the gut Increases the content of beneficial bacteria in the gut |
(185) |
| Inositol | Regulates thyroid hormone synthesis by forming H2O2 in thyrocytes Involved in TSH signaling pathway |
(187) |
| L-carnitine | inhibit thyroid hormone entry into the nucleus of hepatocytes, neurons, and fibroblasts | (186, 187) |
| Probiotics |
Lactobacilli and Bifidobacteriaceae supplementation increase levothyroxine availability Reduce thyroid hormone serum fluctuation Increase the availability of bacterial enzymes sulfatases and ß-glucuronidases that regulate iodothyronines deconjugation |
(188, 189) |
TRH, thyrotropin-releasing hormone; TSH, thyroid stimulating hormone; GPx, glutathione peroxidase; H2O2, hydrogen peroxide.