How to Test For An Iodine Deficiency at Home

Some people may be curious as to whether or not they are actually deficient in iodine.

 In 2008, researchers concerned about the growing threat of iodine deficiency analyzed 88 samples of iodized table salt—the main supply of this critical micronutrient for most people. (1) Less than half of those tested contained amounts of iodine sufficient for optimal health.

Coupled with the trend of reduced “iodized” salt consumption, rates of iodine deficiency are now reaching epidemic levels.

In the developed world, iodine deficiency has increased more than fourfold over the past 40 years. Nearly 74% of normal, “healthy” adults may no longer consume enough iodine.” (2)(3)

Iodine plays vital role in thyroid function and is linked to obesity, cognitive impairment, heart disease, psychiatric disorders, and various forms of cancer. Iodine can also help ward off breast cancer and fibrocystic breast disease. Iodine is one of the most common nutrient deficiencies in the world, and here is an easy way you can test for an iodine deficiency at home. (4)

One of the most popular ways to test for iodine deficiency at home is the iodine patch test. The Iodine Skin Patch Test measures how quickly the body absorbs iodine through the skin.

1. Get a solution or tincture of iodine (the orange solution, not the clear one.) Thyroid Warrior would work just fine.

2. Paint a 3-inch by 3-inch square on your abdomen, inner thigh or inner forearm. Allow it to dry before touching anything, as it will stain.

3. Monitor the patch over the next 24 hours for color changes.

If the patch still exists 24 hours later, the results are normal. If the patch disappears or mostly disappears in less than 24 hours, it is supposed to indicate some degree of deficiency. In fact, significant lightening or disappearance in less than 18 hours is said to indicate moderate to severe iodine deficiency and suggest a need for supplemental iodine.

How Accurate is the Iodine Skin Patch Test?

Over 100 years ago, the application of iodine to the skin was used extensively for iodine supplementation and was found to be an effective form of supplementation. (8) In 1989, scientist tested the amount of iodine absorbed through the skin of 24 adult males and also found the iodine to be absorbed through the skin and effective. (5)

Although several recent studies have demonstrated increases in iodine levels through skin absorption suggesting the result of this test may reflect a deficiency or adequacy of iodine, a lot of other factors may suggest otherwise. (5)(6)(7)

A number of factors play a role in the disappearance of the yellow color of iodine from the surface of the skin. The evaporation of iodine can also be affected by ambient temperatures and atmospheric pressure. If you’re looking for an accurate way to test your iodine status, schedule an iodine loading test.

Final Thoughts on Iodine

In a world full of endocrine disruptors, misguided diets, and daily stressors, it is very easy for people to fall below their individual nutritional intake requirements.  Given iodine’s responsibilities inside and outside the thyroid, its sufficiency is so important for all men, women, and children. When symptoms of iodine deficiency start to emerge follow these guidelines to properly supplement with iodine.


1. Dasgupta PK, Liu Y, Dyke JV. Iodine nutrition: iodine content of iodized salt in the United States. Environ Sci Technol. 2008 Feb 15;42(4):1315-23.

2. Gunton JE, Hams G, Fiegert M, McElduff A. Iodine deficiency in ambulatory participants at a Sydney teaching hospital: is Australia truly iodine replete? Med J Aust. 1999 Nov 1;171(9):467-70.

3. Hoption Cann SA. Hypothesis: dietary iodine intake in the etiology of cardiovascular disease. J Am Coll Nutr. 2006 Feb;25(1):1-11.


5. Miller KL, Coen PE, White WJ, Hurst WJ, Achey BE, Lang CM. Effectiveness of skin absorption of tincture of I in blocking radioiodine from the human thyroid gland. Health Phys. 1989 Jun;56(6):911-4.

6. Zimmermann MB, Crill CM. Iodine in enteral and parenteral nutrition. Best Pract Res Clin Endocrinol Metab. 2010 Feb;24(1):143-58. doi: 10.1016/j.beem.2009.09.003.

7. Tomoda C, Kitano H, Uruno T, Takamura Y, Ito Y, Miya A, Kobayashi K, Matsuzuka F, Amino N, Kuma K, Miyauchi A. Transcutaneous iodine absorption in adult patients with thyroid cancer disinfected with povidone-iodine at operation.

8. Nyiri W and Jannitti M. “About the fate of free iodine upon application to the unbroken animal skin. An experimental study.” J Pharmacd Exp Ther, 1932; 45:85-107.