"On one dry-skinned hand, you might have overt symptoms. You may have trouble staying lean, which might be a direct result of thyroid inefficiency. You might have mysterious fatigue. You may suffer from unexplained autoimmune diseases, or have the aforementioned dry skin, be constipated, or suffer from depression.
A malfunctioning thyroid, courtesy of a lack of iodine, might also play a role in heart disease, psychiatric disorders, and various forms of cancer, including breast cancer."