Iodine is an essential mineral found in such foods as seaweed, cod, yogurt and most of all, in salt. It is mostly found in the ocean, which is why it tends to occur naturally in some seafood. The thyroid needs iodine to make hormones and iodine deficiency is a common global problem. Iodine also plays a major role in the development of the nervous system and is thus very important for both mother and baby during pregnancy. It is also possible that iodine deficiency might also increase the risk of cancers such as prostate, breast, endometrial, and ovarian cancer. It is also used in cases of diabetes, heart disease and stroke.