Multiple nutritional factors and thyroid disease, with particular reference to autoimmune thyroid disease

Area of Science:

• Endocrinology
• Immunology
• Nutritional Science

Background:

• Autoimmune thyroid diseases (AITD), such as Hashimoto's thyroiditis and Graves' disease, are common autoimmune conditions.
• Their development is influenced by genetic susceptibility, environmental factors (including nutrition), and immune system dysfunction.
• Key autoantibodies include those against thyroid peroxidase (TPO) and the thyroid-stimulating hormone receptor.

Purpose of the Study:

• To review the impact of iodine, iron, and selenium on the risk, pathogenesis, and treatment of thyroid disease.
• To synthesize current evidence on the role of these essential micronutrients in thyroid health and autoimmunity.

Main Methods:

• A narrative review of publications from PubMed and the Cochrane Library.
• Focused search on the effects of iodine, iron, and selenium in relation to thyroid disease.

Main Results:

• Excess iodine intake can trigger autoimmune thyroiditis due to increased thyroglobulin (Tg) immunogenicity.
• Iron deficiency impairs thyroid metabolism; correcting iron deficiency can improve hypothyroidism symptoms in some patients.
• Selenium, via selenoproteins, plays a vital role in thyroid hormone production and antioxidant defense, with evidence suggesting it can reduce thyroid antibodies and improve outcomes in AITD and postpartum thyroiditis.

Conclusions:

• Maintaining appropriate iodine, iron, and selenium status is essential for overall thyroid health.
• Nutritional interventions targeting these micronutrients may play a role in managing AITD.
• Further research into the precise mechanisms and optimal therapeutic strategies is warranted.