Optimal - The Blog

August 31, 2026

Iodine, Youodine, We all Iodine

Discover the importance of iodine for thyroid health and brain development, sources of iodine, and the risks of deficiency in today's diets.

Iodine is an essential mineral that helps the body make thyroid hormones. These hormones regulate metabolism and other critical functions, and they are particularly important for brain development in babies and children. In adults, most of the body's iodine is stored in the thyroid gland.

Iodine is found in foods such as seaweed, seafood, eggs, and certain types of bread. It is also present in dairy products, meats, fruits, and vegetables, although levels can vary significantly.

Before the introduction of iodized salt in the 1920s, iodine deficiency was common in the US, particularly in areas with low-iodine soil.

While iodine levels have improved over time, recent studies indicate a decline, particularly among women of childbearing age, likely due to changes in diet and food production.

Some people are at a higher risk of iodine deficiency, including those who do not use iodized salt, pregnant women, vegans, and individuals living in areas with iodine-poor soil.

Causes of iodine deficiency disorders

Source: Ahad, Farhana, and Shaiq A Ganie. “Iodine, Iodine metabolism and Iodine deficiency disorders revisited.” Indian journal of endocrinology and metabolism vol. 14,1 (2010): 13-7. This is an open-access article distributed under the terms of the Creative Commons Attribution-Noncommercial-Share Alike 3.0

While most people obtain sufficient iodine from their diet, some individuals may require additional iodine supplements. Seaweed is a natural source of iodine. Research suggests that iodine supplements can help support thyroid function and brain development, even in people with mild deficiencies.

Some multivitamins also contain iodine to help maintain proper levels. However, excessive iodine intake can be harmful, especially for people with thyroid conditions, so it is essential to consult your healthcare practitioner to check your iodine status before taking supplements.