(The Best Years in Life) Iodine is an overlooked mineral, yet its importance to overall health and well being cannot be overstated. Iodine is critical for the formation of thyroid hormone. People who have difficulty losing weight even though they eat small portions of health promoting foods are probably short on iodine. Iodine deficiency can lead to dull brittle hair, balding, lack of skin tone, low energy levels, difficulty dealing with environmental temperature change, poor concentration, constipation, depression, and extreme fatigue. And there is one more manifestation of low iodine. Scientists now believe that iodine deficiency plays a role in the development of breast cancer. Read More.