The thyroid is a complex gland that requires multiple nutrients to function properly, especially specific minerals. These nutrients help not only produce the thyroid hormones— T3 and T4— but they can also help facilitate specific metabolic processes in the body and help control when these processes are active or non-active. Having too much or too little of the following five minerals can cause thyroid dysfunction, which can have a direct effect on your metabolism and your body’s ability to be in an anabolic (muscle-building) or catabolic (muscle-wasting) state. Keep reading to find out if these minerals are part of your nutrition plan.
This mineral is mostly obtained from iodine-rich foods, including vegetables grown in iodine-rich soil, or from drinking water. Iodine is also found in seaweeds such as wakame, nori or mekabu. Iodine is essential to the formation of thyroid hormones, when it combines with tyrosine to form T4 and T3 through a series of reactions. A proper balance of iodine in the body is essential to maintaining a healthy thyroid and normal thyroid hormonal balance. Too little or too much iodine can both result in thyroid dysfunction. It is recommended to consume approximately 1.1 mg per day of iodine.
This mineral is essential to the conversion of T4 to T3, which is the active and free form thyroid hormone that can have a direct effect on metabolism. This mineral is needed for proper absorption of iodine by the cells, and is an essential co-factor in enzymes involved in thyroid hormone production. Without magnesium, many of the thyroid enzymes that make thyroid hormone simply could not function. Hypothyroidism has been associated with low magnesium levels with low iodine uptake and low need of muscle repair, while hyperthyroidism has also been associated with low magnesium and increased need of muscle repair due to musculoskeletal changes, which leads to increased production of thyroid hormones. Aim to get the required daily magnesium needs of 400 mg per day.
Zinc is essential for many biochemical and enzymatic processes in the body including the thyroid. Research has shown that both hypo and hyperthyroidism can be caused from zinc imbalances, which can impact both T4 to T3. Thyroid imbalance can further impact zinc availability and absorption in the body. Zinc is essential for the T3 receptor to adopt its biological active form. Lack of zinc can result in a lack of T3 activation, while too much zinc may suppress thyroid function by interfering with copper absorption. This mineral can be found in pumpkin seeds, kidney beans, spinach and flaxseeds. The recommended daily intake for zinc is 11 mg a day.
This mineral is also involved in the conversion of T4 to T3, removing an iodine molecule. Without this conversion, no activation of T3 would be possible. Selenium deficiency can lead to an imbalance of T4 to T3, giving way to inactive thyroid function and a slowed metabolism. Selenium has also been shown to protect the thyroid gland from oxidative damage that occurs when hydrogen peroxide is generated to make thyroid hormone. Without adequate selenium, high iodine levels lead to destruction of the thyroid gland cells. This may be because a selenium deficiency makes the enzyme glutathione peroxidase less effective. The recommended daily intake for selenium is 55 mcg per day, and it comes from a supplement or from walnuts, beef, poultry or fresh and salt-water fish.
This mineral is an important part of the balance of minerals including zinc, copper and selenium that are essential for thyroid hormone production. Manganese can also play a role as a co-factor assisting in other metabolic processes in the body. One study showed that the mean values of manganese in serum samples of females with hyperthyroidism was significantly higher, while lower values of manganese was observed in serum samples of hypothyroid patients. Rich sources of manganese can be found in whole grains, nuts and leafy vegetables.
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