Top 3 Thyroid-Supporting Nutrients
The thyroid gland is a significant regulator of cellular metabolism. As a result, it influences numerous physiologic processes including:
- Development and growth
- Lipid and carbohydrate metabolism
- Cardiac myocyte activity
- Cognitive, liver, and kidney function
Because of its broad impact on health, it is clinically important to support the function of the thyroid gland. One way to do this is by supplementing the diet with the nutrients required to synthesize thyroid hormone, especially iodine, L-tyrosine, and selenium.
Worldwide, iodine deficiency is correlated with poor thyroid function. Many studies have shown that a diet rich in iodine or iodine supplementation supports healthy thyroid function. The thyroid hormone thyroxine or T4 is 65% iodine by weight. The Recommended Dietary Allowance of iodine per day for adults is 150 mcg and the tolerable upper intake level is believed to be 1,100 mcg per day for adults. The average recommended amount to support thyroid function is between 150 to 600 mcg per day depending on the diet and health status of the individual. Like some other minerals such as potassium, supplemental iodine in high dosages can cause stomach upset and is an important side effect to understand and prevent by taking it with the largest meal. Excess iodine is contraindicated for patients with Hashimoto’s thyroiditis.
Selenium is as important as iodine for supporting thyroid function. The thyroid gland contains more selenium by weight than any other organ in the human body. Selenium is required for the production of the T3 thyroid hormone. Without selenium, there would be no activation of thyroid hormone. For this reason, it’s clinically necessary to correct selenium deficiency. Research has demonstrated an effective form of supplemental selenium for the thyroid is selenomethionine. The average recommended amount when supplementing selenium is 200 mcg per day for adults. High doses of selenium (more than 400 mcg per day) is typically not recommended.
Thyroid hormones are synthesized from the amino acid tyrosine. It is usually included in thyroid support formulas for this reason. Tyrosine is also converted into catecholamines (“fight-or-flight” hormones, including dopamine, norepinephrine, and epinephrine) in the brain. Entry of circulating tyrosine into the brain is dependent on the ratio of tyrosine to other large amino acids in the circulation since they all compete for the same carrier to move across the blood-brain barrier. Supplemental dosing of tyrosine has been shown to increase the level of tyrosine in the brain, and for this reason, high doses of supplemental tyrosine are not recommended. The typical amount found in thyroid support formulas is 250 -500 mg, which, when taken with other protein foods as recommended, is more likely to be utilized as needed in the thyroid glan and other tissues, and less likely to cross the blood brain barrier.
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