Iodine: The Underrated Essential Mineral and Its Surprising Health Benefits
Iodine is a mineral that is found naturally in soil and ocean water. Many salt-water and plant foods contain iodine, which is most widely available in modern diets in iodized salt. Unless you eat seafood daily, you probably need to get more.
Iodine is essential for optimal thyroid health, a small gland at the front of your neck. Upon receiving a signal from the thyroid-stimulating hormone (TSH), made by the pituitary gland, the thyroid gland uses iodine to make the thyroid hormones T3 and T4. If your body is low in iodine, it can’t make enough of these hormones, a condition known as hypothyroidism. To compensate, the thyroid works harder to make more, which can cause the cells to grow and multiply, eventually leading to a goiter or enlarged thyroid. The presence of adequate circulating T3 and T4 feeds back to the hypothalamus and pituitary, decreasing TSH production. Even a tiny change in circulating thyroid hormone levels is sufficient to alter brain function.
Thyroid hormones regulate several physiologic processes, including growth, development, metabolism, and reproductive function. Symptoms of hypothyroidism, such as weight gain and reduced brain development, are often associated with iodine deficiency. Studies show that the hippocampus, the part of the brain that controls long-term memory, appears smaller in people with low thyroid hormone levels. Iodine also has been shown to improve immune system function and protect against brain damage. It is essential during pregnancy to ensure proper fetal and infant brain development.[1] In fact, iodine deficiency is the leading cause of preventable brain damage.
Interestingly, a 2009 study showed that electromagnetic fields emitted by mobile phones may cause some detrimental effects on thyroid function.[2] TSH levels in mobile users significantly differed from non-users, a hallmark of thyroid dysfunction. Minor degrees of thyroid dysfunction with a compensatory rise in TSH may occur from mobile phone usage, which could explain the prevalence of thyroid dysfunction.
Symptoms of iodine deficiency and hypothyroidism are similar and include low body temperature (i.e. feeling cold when others do not), chronic fatigue, muscle weakness, loss of libido, depression, weight gain, hair loss, dry skin, and memory problems.
Much of the U.S. was iodine deficient a century ago, and goiter was endemic. To combat this, the government introduced iodized salt in the 1920s, and since the 1940s, the U.S. population has been considered iodine sufficient. But U.S. dietary iodine has decreased by 50% since the 1970s due to the war on salt and the rise of processed foods.[3] Salt has been demonized for decades (erroneously) as a cause of heart disease, so people have reduced their intake of iodized table salt. Meanwhile, kosher and sea salt, which have become more popular, are not iodized. Finally, the vast majority of salt intake in the U.S. is from processed foods, which almost universally contain non-iodized salt. Currently, the majority of U.S. dietary iodine intake is from dairy, which comes from cattle feed additives and the use of iodophor cleansers by the dairy industry.
Seafood, seaweed, and eggs are the most common sources of dietary iodine, and many people don’t regularly incorporate these foods into their diets, leading to widespread iodine insufficiency. Meanwhile, physically active people need to pay extra attention to their iodine intake since the mineral is lost through sweat.[4] Taking 100-200 mcg of iodine as potassium iodide or kelp powder is a relatively safe and easy way to help ensure optimal hormone health, immunity, and brain health. If you have hypothyroidism or hyperthyroidism (overactive thyroid), iodine supplementation could lead to complications, so talk to your doctor about how to treat those conditions.
To help ensure optimal hormone health, immunity, and brain health, THRIVE contains 200mcg of iodine.
[1] https://pubmed.ncbi.nlm.nih.gov/36321429/
[2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3243874/
[3] https://www.sciencedirect.com/science/article/pii/S2376060520303680