A new study in the Harvard Undergraduate Research Journal by Shubha Bhat addresses the basic assumption of all salt iodization programs: whether having iodized salt available to the population translates into better iodine nutrition and the health benefits flowing from eradicating IDD. The finding: iodized salt works.

"The finding will buttress efforts to expand India's 51% availability of iodized salt -- a level that has given India the dubious title of having the largest population of unprotected newborns each year.

"(I)t is crucial to establish a causal link between access to iodized salt and child health. This study examined household salt iodine concentration, anthropometric outcomes, and birth histories of over 18,000 children from the 1998 India National Family Health Survey. ... Innovative district-level instruments were constructed using Geographic Information Systems to predict salt iodine concentration in households and targeting efforts of the government. The 2SLS estimate revealed that increasing the iodine level in salt led to a 1.168 standard deviation increase in height-for-age (p<0.05), a 15.9% decreased likelihood of having below-average birth weight (p<0.05), a 18.6% increased likelihood of having above-average birth weight (p<0.05), and a 2.8% increase in child survival (p<0.10)."