Salt & Human Health: Iodine Deficiency

Using as examples the role of salt in combatting lymphatic filariasis and iodine deficiency, the cover story of the June issue of Geotimes devoted six pages to "Salt of the Earth: the pubilc health community employs a mineral to fight infectious disease." Pointing out that its economy and ubiquity make salt the "ideal vehicle" to fortify with minerals or medications, author Cassandra Willyard concludes: "The saltshaker has become one of the most powerful weapons in the public health arsenal."

The article recounts the pioneering public health efforts to combat iodine deficiency by iodizing salt, quoting Venkatesh Mannar, executive director of the Ottawa-based Micronutrient Intitiative, explaining that salt is the "food that comes closest to being universally consumed." Salt is preferred because "the risk of overdose is minimal because everyone eats a predictable amount."

Building on the success of salt iodization, salt was fortified with other additives, first fluoride to prevent dental caries and then chloroquine to prevent malaria and most recently DEC (diethylcarbamazine) to combat lymphatic filariasis. Willyard featured the World Health Organization's ongoing work with DEC-fortified salt in Haiti and Guyana.

The article also broaches the question of the adequacy of iodine nutrition in the U.S. where substitution of processed foods using plain salt for home-cooked meals using iodized salt has led to a gradual decline in iodine intake levels. Willyard includes the Salt Institute's views, noting "officials may think about adding iodized salt to processed foods, Hanneman says. The important things, he adds, is to keep monitoring."

Posted by Dick Hanneman at 03:47 PM | Permalink

Thanks to a global campaign by UNICEF and its partners (which include the Salt Institute) about 70% of households around the world are now receiving iodine through iodized salt, and 34 countries have universal salt iodization, according to a new UNICEF report, Sustainable Elimination of Iodine Deficiency,issued June 26. As recently ago as two decades, only 20% of households were receiving sufficient levels of iodine.

In 1990, IDD was a public health problem affecting an estimated 2 billion people. Today, that number has been pared to about 400 million, half of them in India. Each year, 38 million children are born at risk of iodine deficiencies that can penalize them 10-15 IQ points in mental capacity.

Posted by Dick Hanneman at 07:16 AM | Permalink

For the past two years, more than 50 economists under the aegis of the Copenhagen Consensus have been studying the 30 most promising public health interventions to help policy-makers prioritize public health investments. They filed their report today and issued a news release summarizing their findings.

The top three:

1. Combatting micronutrient malnutrition by fortifying foods with vitamin A and zinc.

2. Completing the Doha round of international trade liberalization.

3. Iodizing salt and fortifying foods with iron.

Micronutrient malnutrition ("hidden hunger") is the clear winner with two of the top three "solutions." Fortifying with vitamin A and zinc return $17 for every dollar invested. The benefits of iodizing salt are $9 for every dollar invested.

With the candidates for the Democratic US presidential nomination competing to bash free trade, #2 may gain some political salience. But investing in micronutrient fortification -- including universal salt iodization -- should be high on the public health agenda.

Posted by Dick Hanneman at 05:31 PM | Permalink

Australia and New Zealand have a problem with eroding levels of iodine nutrition for which the universal consensus solution is using iodized salt. Responsibly, FSANZ, the nations' joint regulatory body, has concluded that bakers should be mandated to use iodized salt in their bread. If that proves insufficient, the universe of foods can be expanded. Today, the Salt Institute endorsed the approach for Australia, as it had done earlier for New Zealand.

Replacing plain salt with iodized salt in bread is technologically feasible and well-tested. Relying on iodized salt, of course, is the international standard, and a step-wise approach preserves the flexibilty to go back and fine-tune the rule if ongoing monitoring shows bread alone isn't enough. But it may be enough. FSANZ's analysis estimates that currently 40% of the population is either slightly or seriously iodine-deficient. Using iodized salt in bread should reduce that to less than 10%.

Posted by Dick Hanneman at 04:00 PM | Permalink

In the article, "Technological issues associated with iodine fortification of foods," authors Winger, Konig and House describe some of the potential interactions of iodine compounds with foods. This article is of considerable interest because it goes into a range of possible problems associated with high-level iodine fortification - that is, the addition of iodine compounds directly to the finished foods.

Although the authors attempt to make it clear that the negative consequences of iodine fortification of foods would only occur at high levels of fortification and would never be the result of using iodized salt, they do not unequivocally state that, for all intents and purposes, whole formulated food products would never be iodized at levels that would impact the color, flavor or functionality of those foods.

If whole, formulated foods will never be iodized to those levels which can impact on the quality of the food, then the whole issue becomes moot and should not be confused with the use of iodized salt in food products.

Iodized salt can be used in formulating all food products without any fear of reducing quality.

Perhaps it would have been useful for the authors to have made that simple statement of fact.

Posted by Mort Satin at 10:28 AM | Permalink

The New Zealand Bakery Association has blasted FSANZ, warning that its new requirement of iodized salt in bread "will be expensive, claiming there are not a lot of facilities to process iodised salt in the country." The bakers apparently duped foodnavigator.com writer Charlotte Eyre on that point and another: that "iodine is a nutrient commonly found in salt."

Noting that "half truths are the most insidious," the Salt Institute responded, defending the FSANZ decision and pointing out that:

Surely the bakers have better fights to fight.

Posted by Dick Hanneman at 09:58 AM | Permalink

As in the U.S. use of iodized salt by food processors in New Zealand has been voluntary. No longer when it comes to bread. The joint Australian-New Zealand Food Standards Agency (FSANZ) has just issued a directive mandating use of iodized salt in breadmaking to reverse the country's declining iodine sufficiency status -- a condition also observed in the U.S. and Australia. FSANZ will consider similar requirments in Australia in a separate rule-making.

Posted by Dick Hanneman at 01:57 PM | Permalink