You may know iodine only as an antiseptic used to treat small cuts and scrapes or an ingredient found in table salt. In reality, iodine is the reason why your body functions. Iodine is necessary to make thyroid hormones, which every cell in the body depends upon to regulate its metabolism. Cells in the thyroid, a small gland weighing less than one ounce and located in the front of the neck, are the only cells capable of absorbing iodine. Thyroid cells capture iodine and combine it with tyrosine—an amino acid—to produce thyroid hormones that are then released into the bloodstream. When the body lacks iodine, the thyroid gland become enlarged, a condition called goiter.