Thyroid doctors clash over iodine nutrition for expectant mothers

Last October, the Public Health Committee of the American Thyroid Association published recommendations on iodine supplementation for pregnant and lactating women in North America. Noting that the World Health Organization had increased its recommended daily intakes to 250 micrograms of iodine daily and that 7.3% of pregnant Americans are ingesting less than 50 micrograms -- the minimum safe level -- the ATA called for all pregnant and lactating women to take iodine supplements of 150 micrograms/day.

Not so fast, says Kevin Sullivan of Emory University, a board member of the International Council for the Control of Iodine Deficiency Disorders. Dr. Sullivan argues in a letter published in the current issue of the journal Thyroid that many women don't take supplements and, even if they started when they learned they had become pregnant, irreversible brain damage may already have been done to their unborn baby. He argued that "all household salt (as well as salt substitutes) and salt used in the food industry" should be iodized. He explained:

The Committee should be applauded for their efforts to prevent irreversible fetal brain damage as a result of iodine deficiency. While an important and useful step, the iodine supplementation during pregnancy recommendation has some limitations. First, currently the Institute of Medicine recommends multivitamins for some groups of pregnant women and the recommended vitamins and minerals do not include iodine, therefore many prenatal multivitamins do not include iodine. The Public Health Committee recommended efforts to encourage manufacturers to include iodine in all vitamin and mineral preparations for use during pregnancy and lactation. Second, many women will not use supplements on a regular basis as has been found with folic acid supplementation. Women who do not use supplements on a regular basis tend to be younger, of lower education, and of certain ethnic/racial groups. In addition, much of the damage caused by iodine deficiency occurs early in the pregnancy, therefore, by the time a woman realizes she is pregnant and seeks prenatal care, damage may have already occurred.

It would seem that the focus of preventing the negative effects of iodine deficiency in the developing fetus should focus on all women of childbearing age. Efforts should be placed on fortification of salt for human consumption as recommended by the International Council for Control of Iodine Deficiency Disorders (ICCIDD ), United Nations International Children's Emergency Fund (UNICEF ), and WHO and implemented in many countries. In the United States, all household salt (as well as salt substitutes) and salt used in the food industry should contain iodine at levels to assure an adequate iodine intake in the vast majority of the population. Through careful study of urinary iodine levels, the iodine content of salt and salt substitutes can be adjusted to assure that there is not too much or too little iodine in the diet, similar to the approach used in Switzerland. To prevent excess iodine intake, the iodine levels in other foods, such as dairy products and bread, may need to be regulated.

Iodizing salt substitutes -- like potassium chloride and "sea salt." Now, THAT's an interesting idea. For a salt industry perspective, see the Salt Institute website or that of EuSalt . The salt industry is part of a global Network for the Sustained Elimination of Iodine Deficiency .