Iodine is essential for the proper functioning of a normal metabolism.  We get iodine from our diet.  The thyroid gland contains tiny pumps called Sodium Iodide Symporters (NIS) that concentrate the iodine in our thyroid glands.  The thyroid gland needs iodine to make thyroid hormones.  As you know, thyroid hormones are necessary for a healthy metabolism.  Thus, if we don’t get enough iodine in our diets we can easily suffer the effects of a slower metabolism, which include weight gain, impaired mental function, fatigue, and infertility!

Interestingly, the breast also has the NIS pumps so that it can concentrate iodine in the breast in order to supply nursing babies with iodine.  It is extremely important that pregnant mothers have enough iodine in their systems during pregnancy in order to prevent stunted mental and physical growth of the baby.  Some areas of the world have diets more deficient in iodine than others.  People with diets severely deficient in iodine can have children with cretinism which is severe mental and physical growth retardation due to inadequate thyroid hormone levels. Iodine deficiency can increase cancer of the thyroid, breast, ovary, uterus, stomach, and esophagus.  It can also contribute to cysts in the breasts (as in fibrocystic breast disease) and ovaries!

The United States and many other countries add iodine to table salt to combat iodine deficiency.   However, some people are on low salt diets or choose to use non-iodized salt.  In addition, chlorine (pool water, city water, spa water), fluorine (from toothpastes), and bromine (from certain baked goods and certain soft drinks) can take the place of iodine in the body, leaving the body relatively deficient.  Most people in the United States have less than optimal iodine sufficiency.

Deficiency is a relative term.  How bad would you have to feel before you called yourself sick?  If you only had 95 % energy would you say you were sick?  What about 90%, or 80%.   Since we know that severe iodine deficiency can cause severe problems, it makes sense that mild deficiency can cause more mild problems.  However, we don’t want to have any problems when it comes to something easily and totally avoidable like iodine deficiency.  The US recommended daily intake is 150 mcg/day.  However, Japanese people often consume 50-80 times that much (5-13 mg/day), primarily from seaweed, and have less of the health problems associated with iodine deficiency.

Some people have hypothyroidism because they are deficient in iodine, while others are hypothyroid because their thyroid glands can’t make enough thyroid hormone even though they have enough iodine on board.  How can you tell the difference? If patients have hypothyroidism (high TSH and low T3 and T4 ) and no TPO antibodies then the high TSH is usually due to iodine deficiency (as opposed to Hashimoto’s)!

Urine tests can be done to assess a patient’s iodine levels.  Iodine supplements can be used to promote optimal iodine sufficiency.  People should not take a lot of iodine if they have a hot nodule that is causing them symptoms of palpitations.

You can see a doctor to help you assess your iodine level and help you find an iodine supplement as well, if necessary.