Iodine Deficiency Disorders

The Most Damaging Effect of a Lack of Iodine is on Brain Function

Mar 14, 2009

Iodine deficiency is a major health problem. The effect of low iodine intake on the production of thyroid hormone has a direct impact on brain function and development.

“On a worldwide basis, iodine deficiency is the single most important preventable cause of brain damage.” This statement is from the 2007 publication “Assessment of Iodine Deficiency Disorders and Monitoring their Elimination” by the United Nations Children's Fund (UNICEF), the International Council for the Control of Iodine Deficiency Disorders (ICCIDD) and the World Health Organisation (WHO).

According to this publication, iodine deficiency is an easy and inexpensive nutrient disorder to prevent. However, the world is facing a major health problem; iodine intake levels are declining, even in countries such as the United States; therefore, iodine deficiency disorders may be increasing.

Iodine deficiency affects one in three people worldwide; with two billion people having inadequate iodine intakes. Iodine deficiency affects brain development and brain function.

Iodine Deficiency Linked to a Range of Conditions

The most common condition related to iodine deficiency and therefore a low thyroid hormone level is goiter or hypothyroidism. However, there is a range of conditions termed “iodine deficiency disorders”.

Low iodine levels affect fetal development and children the most. Iodine deficiency causing low thyroid hormone levels is the principal factor responsible for damaging the developing brain and affecting brain function in fetal development and childhood. The most critical period for iodine deficiency damage is from the second trimester of pregnancy to the third year after birth.

Communities that suffer from iodine deficiency have a poor quality of life, with little chance of achievement and a perpetuation of underdevelopment. In areas of severe iodine deficiency people may have an intelligence quotient (IQ) of up to 13.5 points below those from an iodine-sufficient area, according to the UNICEF, ICCIDD and WHO 2007 publication.

Low Iodine Intake is a Primary Factor in Deficiency

Low iodine intake is the primary cause of iodine deficiency disorders. A daily iodine intake of less than 20 micrograms per day will cause iodine deficiency symptoms to occur.

In order to overcome this major health problem countries have started iodized salt programs (as in the United States) or introduced iodized salt to breads (as in Australia). However, a recent study by Purnendu K. Dasgupta et al, “Iodine Nutrition: Iodine Content of Iodized Salt in the United States”, published in the 2008 Environmental Science & Technology journal, Volume 42, issue 4 revealed the levels of iodine in salt are below the United States Food and Drug Administration’s (USFDA) recommended iodine content.

Other causes of a low iodine intake and increased iodine deficiency risk include the reduced use of iodine in animal feeds and milk production, and an increased health awareness of a low salt diet.

Increased intake of iodine foods is necessary on an individual basis. This can become complicated with varying amounts found is soils. The oceans are a source of iodine so foods such as seaweed and fish are classed as iodine foods.

References:

Braun, L., & Cohen, M. (2005). Herbs & Natural Supplements- An evidence- based guide. Sydney: Elsevier Mosby.

de Benoist, B., McLean, E., Andersson, M., & Rogers, L. (2008). Iodine deficiency in 2007: global progress since 2003. Food Nutr Bull, 29(3), 195-202.

Eastman, C. (2005). Iodine Supplementation: The benefits for pregnant and lactating women in Australia and New Zealand. O & G, 7(1), 65-66.

Patrick, L. (2008). Iodine: deficiency and therapeutic considerations. Altern Med Rev, 13(2), 116-127.

The copyright of the article Iodine Deficiency Disorders in Vitamins & Minerals is owned by Melissa Peterson. Permission to republish Iodine Deficiency Disorders in print or online must be granted by the author in writing.