Your thyroid is a butterfly-shaped gland that sits near your vocal cords and produces the T3 and T4 hormones that control your metabolism. To make these hormones, your body uses iodine -- about 80 percent of the iodine you consume is used by your thyroid. If your diet is deficient in iodine, or you have an underactive thyroid, known as hypothyroidism, eating raw cruciferous vegetables such as cabbage can further suppress your thyroid hormone function.