Meredith Bull, ND, is a licensed naturopathic doctor with a private practice in Los Angeles, California. Iodine is an essential mineral, meaning your body needs it to function properly. You can't produce it on your own and must ingest it through your diet or as a supplement.
Iodine is consumed by mouth and is quickly absorbed in the stomach and small intestine. It travels through the bloodstream and from here, iodine receptors (located in the thyroid) bind to it and take it in.
An iodine deficiency results in low thyroid hormone levels. In response, your pituitary gland makes excess thyroid stimulating hormone (TSH) to make up for these low levels. TSH normally stimulates the thyroid gland to produce and release T4 and T3.
In fact, with a thyroid disorder, a low iodine diet is often recommended. If you have to follow a very low salt diet due to other health issues, you may need iodine supplementation. Do not use iodine supplements unless you are diagnosed with iodine deficiency.
When an iodine deficiency results in low thyroid hormone levels, your pituitary gland makes excess thyroid stimulating hormone (TSH) to compensate for the low thyroid hormone levels. TSH normally stimulates the thyroid gland to produce and release T4 and T3. Excess TSH overstimulates the thyroid gland. In response to this, the thyroid gland becomes enlarged, yet still cannot function adequately in the absence of sufficient iodine. This change is described as goiter. 6
If you have low iodine levels, the symptoms of thyroid dysfunction can develop within a few weeks and include a variety of conditions:
Common sources of iodine include: Salt: Iodized salt contains an average of 45 micrograms of iodine per gram. This concentration may differ depending on the manufacturer. For precise amounts, check the label’s nutritional information. Food: Iodine is a component of seafood, milk, vegetables, and fruit.
Measuring Iodine Levels. Iodine levels are not measured in the blood, but they can be measured in the urine. Urine measures of iodine are considered a reflection of iodine intake. Normal urinary iodine concentrations range between 100 and 200 micrograms per liter.
Inadequate iodine prevents your body from making enough thyroid hormones. This can cause a variety of symptoms, including weight gain, diminished energy, sleepiness, trouble concentrating, depression, constipation, feeling cold all the time, menstrual irregularities, and problems with blood sugar. 4
Common sources of iodine include: 1 Salt: Iodized salt contains an average of 45 micrograms of iodine per gram. This concentration may differ depending on the manufacturer. For precise amounts, check the label’s nutritional information. 2 Food: Iodine is a component of seafood, milk, vegetables, and fruit. Fish and seaweed are the foods richest in iodine— one serving of fish contains about 90 micrograms of iodine and one serving of seaweed contains about 200 micrograms of iodine. 3 Supplements: Vitamins and supplements vary in their iodine content, and you can find the specific amount of iodine on the label. If you use any type of vitamin or supplement, be sure to let your doctor know If you have a medical condition–do not use supplements before consulting with your doctor.
Iodine is a vital component of thyroid hormones, which is the mineral’s most important and well-understood function. Your thyroid gland makes the thyroid hormones thyroxine (T4) and triiodothyronine (T3), both of which contain iodide (a form of iodine). 3