Thyroid hormones

Thyroid hormones are produced by thyroid glands. T3 and T4 are thyroid hormones that are made up of iodine and tyrosine. Less intake of iodine results in less production of T3 and T4 which may lead to a medical condition called hypothyroidism. Greater production of thyroid hormones leads to hyperthyroidism.
Function.
Thyroid hormones control the metabolism of the body. They act to increase the production of proteins, basal metabolic rate and growth hormone.