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Iodine: Do You Need More?

If you have a sluggish thyroid, low energy, or other health concerns, including asthma or fibrocystic breast disease, iodine supplements could help you feel better.

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In her mid-40s, Michelle found herself feeling extremely tired. She was diagnosed as being hypothyroid, or having low thyroid gland activity, and initially treated with a synthetic thyroid hormone. Her energy levels improved for several months, then began to wane.

A second physician changed Michelle’s prescription to a natural thyroid product (Armour Thyroid) containing both thyroid hormones-thyroxine and triiodothyronine-and thyroid-stimulating hormone. Her energy levels rebounded and remained high for the next three years, and during this time she also lost 25 pounds. Then, as she approached age 50, her energy levels again started to decrease.

By this time, Michelle was consulting a nutritionally oriented physician. He kept her on the natural thyroid medication, but added supplemental iodine. After several months, her energy levels were back to normal. Michelle was able to balance work, home life, and new outdoor activities, such as hiking and bicycling. Iodine proved to be the key to sustaining Michelle’s energy levels.

What Is Iodine?
Iodine is an essential trace mineral. It’s needed to make thyroid hormones, which regulate metabolism and the body’s ability to burn carbohydrates and fats for energy. Iodine is found in every cell of the body, so it likely has far broader roles in maintaining health. Extreme deficiencies of iodine result in goiter, an enlargement of the thyroid gland (which is located in the neck), but “preclinical” deficiencies may be common, according to some experts. As a supplement, iodine is most commonly found in the form of potassium iodide and sometimes as iodine.

How Does It Work?
Iodine’s biological functions are best understood in terms of thyroid function. The pituitary gland secretes thyroid-stimulating hormone (TSH), which stimulates the recovery of iodine from the blood and orchestrates the use of iodine in thyroid hormones. In turn, the thyroid gland makes thyroxine (T4), which contains four iodine atoms. The iodine-containing enzyme deiodinase converts T4 to triiodothyronine (T3), which contains three iodine atoms and is the most active thyroid hormone. When thyroid hormone levels are extremely low, the pituitary increases its secretion of TSH, which may lead to goiter.

Who May Need More?
Iodine supplements may be beneficial in a variety of circumstances. Here is a look at the top health benefits of iodine.

Thyroid function. Because thyroid hormones depend on iodine, people with low thyroid activity (hypothyroid) may benefit from iodine supplements. The risk of two autoimmune thyroid diseases, Graves’ disease and Hashimoto’s disease, is greater in people who lack iodine. Iodine supplements may enhance the benefits of other treatments for low thyroid function, according to David Brownstein, MD, author of Iodine: Why You Need It, Why You Can’t Live Without It.

Selenium is also involved in making thyroid hormones, and a lack of selenium exacerbates iodine deficiency. The two minerals by themselves may not increase thyroid activity, but they should be included in any treatment for low thyroid activity. Try 1,000 to 5,000 micrograms of iodine and 200 to 300 micrograms of selenium.

Asthma. Several studies have found that large supplemental amounts of iodine can reduce viscous bronchial secretions in adults and children with asthma. The research suggests that iodine plays a role in modulating immune cells and may have anti-inflammatory benefits. Take 1,000 to 4,000 micrograms daily. Start at the lower dose.


Seafoods are the richest natural sources of iodine. Seaweed and bladder wrack are particularly
high in iodine.

Fibrocystic breast disease. Several studies have found iodine supplements helpful in resolving painful breast cysts. Benefits were noted after six to 18 months of supplementation. According to Brownstein, the breasts are a major reservoir of iodine. Try 5,000 to 6,000 micrograms daily.

Blood sugar. Some clinical reports suggest that very large supplemental amounts of iodine may improve blood sugar levels and enhance weight loss. The treatments used 50 to 100 milligrams of iodine-an extremely large amount that should be taken only with a physician’s guidance.

Absorption Issues
Goiter was extremely common in iodine-deficient regions, particularly the Midwest, until iodine-containing (iodized) salt was introduced in 1924. Eating large amounts of cruciferous vegetables (such as broccoli and cauliflower), soy (including tofu), and cassava (also called yucca) may interfere with iodine absorption and therefore thyroid function. Eating modest amounts of these foods will not pose a problem. Worldwide, iodine deficiency affects 749 million people and is the leading cause of preventable brain damage.

If you have a nutritionally oriented physician, ask him to run an iodine-loading test to determine whether you need to take high-dose iodine supplements. It’s a simple test involving taking iodine supplements and measuring urine levels of the mineral.

How Much to Take
The recommended amount of iodine is 150 micrograms daily, with 220 micrograms during pregnancy and 290 micrograms when breast-feeding. However, some physicians have argued that the average Japanese resident consumes many times the recommended amount. Consider increasing your iodine intake by eating more seafood or taking at least 100 micrograms of supplemental iodine.

Product Examples (left to right)

NOW Foods Potassium Plus Iodine boasts iodine from potassium iodide, providing both iodine necessary for healthy thyroid function, plus potassium to help maintain proper water balance in the body.

TriMedica Thyadine provides easily absorbable colloidal iodine from sea kelp along with added homeopathic medicines that address thyroid function and obesity.

Nature’s Way Kelp is collected from kelp deep in the ocean to avoid toxins and heavy metals. Kelp provides an excellent source of easily assimilated iodine.