Hypothyroidism: Nutritional Considerations
The nutritional considerations can help reduce the risk of hypothyroidism or aid in treatment:
- Iodized salt: The use of iodized salt is a well–accepted public health strategy for decreasing the incidence of iodine deficiency disorders, particularly hypothyroidism.
- Gluten–free diet in patients with celiac disease: Hypothyroidism is relatively common in patients with celiac disease. Although evidence is limited, clinical trials found that most celiac disease patients with mild hypothyroidism who strictly followed a gluten–free diet for one year experienced improved thyroid function and a reduced need for thyroid hormone medication.
- Iron supplementation: Iron deficiency may also increase the risk for thyroid disease. Although Western, meat–eating populations have greater iron levels than non–Western populations, some individuals are low in iron. One study revealed that thyroid hormone levels were significantly lower in women with iron–deficiency anemia, compared with women who had normal iron levels. In these patients, iron supplementation (or other treatments for iron deficiency) may be useful. However, iron supplements should be taken apart from thyroid hormone medication (see below).
- When thyroid medication is used, it should be taken on an empty stomach. Meals can decrease the absorption of thyroid hormone, with a particularly noticeable effect from high–fiber meals. Both calcium carbonate and iron supplements can significantly reduce absorption of thyroid hormone and reduce its effectiveness. This may have particular relevance for older women, who are more likely to need thyroid hormone replacement and to be using calcium supplements.