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Iodine - Urine


Iodine is an essential trace element, important for healthy thyroid function, required to produce T3 and T4 thyroid hormones. Whether it is determining how fast your heart beats or how quickly your intestines process your food, thyroid hormones control the speed at which your body cells work. Without these hormones, the body would be unable to convert nutrients into energy.

Iodine is obtained through the diet and good sources include shellfish, dairy products and seaweed. Most people should be able to get all the iodine they need by eating a varied and balanced diet. The majority of iodine that is ingested is excreted via the urine. Measuring the amount of iodine excreted through the urine helps to determine iodine levels in the body.

What might a low result mean?

Low levels of dietary iodine reduce the production of T3 and T4 thyroid hormones. An iodine deficiency in the body affects the functioning of the thyroid gland. An underactive thyroid gland does not produce enough of the hormones thyroxine (T4) and triiodothyronine (T3). Low thyroid hormone levels ultimately slow down the body’s metabolism. An iodine deficiency can also cause a thyroid swelling (a goitre).

What might a high result mean?

Elevated levels of iodine can cause you to develop a goitre, which is when a part of the thyroid gland become enlarged. Excessive levels can also upset your digestive tract, causing burning in the mouth, vomiting and abdominal pain.