Thank you for your question, Pamela. Indeed there is some mixed opinions on this topic. Some research findings provide evidence that iodine can cause health issues as thyroid and autoimmune thyroid conditions. Others show that iodine supplementation can lead to improvement in these conditions.
My opinion is that both conclusions are correct in certain circumstances.
What is the relationship between thyroid and iodine?
Thyroid gland takes iodine, found in many foods, and convert it into thyroid hormones: thyroxine (T4) and triiodothyronine (T3). Thyroid cells are the only cells in the body which can absorb iodine. These cells combine iodine and the amino acid tyrosine to make T3 and T4. Three molecules of iodine are required for the formation of T3. Four molecules of iodine are required to produce T4. Iodine and tyrosine are the building blocks of thyroid hormones. Without enough iodine, thyroid will not be able to produce these hormones.
What is the link between iodine and immunity?
Hashimoto’s is not a thyroid condition. It is an autoimmune condition by which thyroid gland is attacked. 90 % of hypothyroidism is caused by Hashimoto’s.
Iodine has been used effectively therapeutically in pathologies for which the immune system is known to play a role. Iodine is a fantastic way to support immune system. In an iodine-rich environment there’s no bacteria, virus, or other microorganism that can survive. Iodine plays a role in the physiology of the inflammatory response.
Iodine’s ability to revive hormonal sensitivity seems to significantly improve insulin sensitivity. Iodine attaches to insulin receptors and improves glucose metabolism.
By Hashimoto thyroiditis certain antibodies are present. Very often these are increased levels of TPO. Thyroperoxidase (TPO) is an enzyme necessary for the production of both T3 and T4. There is some evidence that consuming iodine will increase the TPO antibodies.
Because of that some people concluded that iodine is not good for Hashimoto’s.
With Hashimoto’s Thyroiditis, the hypothyroid condition is caused by the immune system attacking the thyroid gland, thus leading to destruction of the thyroid gland. So the condition itself has nothing to do with iodine.
If there is selenium deficiency then this can cause oxidative damage and trigger an autoimmune response. Numerous studies have shown an increase in thyroid antibodies in those with a selenium deficiency. Other mineral deficiencies can also play a role in this. In any case, it most likely it is not the iodine itself that triggered an autoimmune thyroid condition, but taking iodine in the presence of certain mineral deficiencies.
Selenium is a mineral that is found in high concentration in the thyroid, and the selenoproteins in that gland are involved in antioxidant defense.
The balance between iodine and selenium is important for thyroid function. It is often helpful to check iodine status before supplementing with iodine. Urinary iodine testing (in the form of 24-hour urine iodine or dried urine iodine test) is the most accurate.
Selenium supplementation is a prerequisite in all patients with elevated anti-thyroid antibody levels and Hashimoto’s thyroiditis. Selenium supplementation is required before giving Iodine to the Hashimoto’s patient.
I cannot too often repeat: there are certain patterns by Hashimoto’s that helps us make generalisations and advice all persons who suffer with Hashimoto’s. Though, every one of us is unique. So, please
- Do not take any supplements before testing for deficiencies. High levels of iodine can actually cause both hyperthyroidism and hypothyroidism.
- Test to confirm that an iodine deficiency is present
- If iodine deficient, think of start supplementing with small doses of iodine. Risk factors for iodine deficiency are low dietary iodine, selenium deficiency, pregnancy, smoking, fluoridated and chlorinated water, and goitrogenic foods. An excellent way to boost dietary iodine levels are sea vegetables and saltwater fish.
- Treat leaky gut first then supplement with iodine. Leaky gut may contribute to vitamin deficiencies because of the ongoing inflammation and damage to carrier proteins.
- Sometimes an increase in symptoms can be due a detoxification reaction due to bromine toxicity. Bromines are common endocrine disruptors and can be found in a number of places in your everyday life: e.g. pesticides, plastics, bakery goods, soda, medications, bromine-based hot tub and swimming pool treatments.
Take home tips:
- do not take iodine by mineral deficiencies which are typical by leaky gut. Heal your leaky gut first
- test for deficiency before supplementing
- start with low doses of iodine
- make sure that there is balance between iodine and selenium