Iron and Thyroid Health
Iron is an essential mineral required for:
- Red blood cell production and oxygen transport
- Thyroid hormone synthesis — the thyroid needs iron to generate T4 and T3 (alongside selenium, which converts T4 into the active T3)
Link to Hyperthyroidism
Researchers have linked low iron levels to hyperthyroidism. The mechanism is not fully established, but iron-deficiency states appear to co-occur with hyperthyroid conditions.
Link to Hypothyroidism
A literature review found iron deficiency is often associated with hypothyroidism, especially in pregnant women.
Food Sources
Generally safe (low iodine):
- Fortified cereals and bread
- Raisins
- Dark chocolate
- Beef, chicken, turkey, pork
- Spinach
- White beans, kidney beans, black beans
Iron-rich but also high in iodine (caution on low-iodine-diet):
- Oysters and fish
- Lentils, chickpeas
- Sardines
- Canned or cured meats
Interaction with Levothyroxine
Iron supplements (e.g., ferrous sulphate) interfere with levothyroxine absorption. Doctors recommend a four-hour interval between taking levothyroxine and iron supplements. Also, some multivitamins contain iron — check labels.