An iodine deficiency has been found to be a common cause of unexpected weight gain for many people. (1) This is because iodine plays a major role in the regulation of the metabolism.
In addition to this, a study by Carlton in 2010 found that four of the main American diets (including the Atkins Diet, the DASH (or hypertension diet), the South Beach diet, and the Best Life diet) were deficient in a whopping twenty-seven micronutrients, including iodine. (2)
When iodine enters the body, it is taken up by the thyroid gland which is located in the front of the neck just below the Adam's apple. The thyroid gland then takes this iodine and converts it into two thyroid hormones known as thyroxine (T4)and triiodothyronine (T3). These hormones are then released into the bloodstream where they travel to every cell in the body where they regulate metabolism. (3) Essentially, the more thyroid hormones the body makes, the faster that person’s metabolism will be.