Within the thyroid follicles, hormones are stockpiled in the form of the glycoprotein thyroglobulin. Before the substances are secreted into the bloodstream through the capillaries, however, they are primarily converted into thyroxine, although smaller amounts of other related hormones are also generated. The quantity of the hormones that are produced chiefly depends upon the amount of thyroid-stimulating hormone released by the pituitary gland. Through an effective feedback mechanism the level of thyroxine within the body usually stays within a steady range, but various conditions, as well as an insufficient supply of iodine in the body, may result in too much or too little production, leading to a variety of disorders.