The thyroid gland 1. Produces thyroxine and calcitonin. Thyroxine, an iodine-containing modified amino acid, causes the body to increase its metabolic rate which is reflected in an increase in oxygen consumption. Abnormal amounts of thyroxine a. The condition is called cretinism.
Goiter is a condition where the thyroid gland is enlarged due to a lack of dietary iodine.
Iodine is needed for the synthesis of thyroxine and an abnormal number of cells are produced in response to this lack. Certain cells in the thyroid produce a hormone that promotes the storage of calcium in bones. This results in a reduction in blood calcium. This hormone is named calcitonin. Its role in humans is open to question.