Toward an ecosocial epidemiological approach to goiter and other iodine deficiency disorders: a case study of India's technocratic program for universal iodization of salt.

The program of universal salt iodization (USI) was intensified in the 1990s. Unfortunately, a recent World Health Organization review finds that there was a global increase of 31.7 percent in total goiter rate from 1993 to 2003. However, the WHO review places only 1 country as severely, 13 as moderately, and 40 as mildly deficient in populations' iodine nutrition, and places 43 countries at optimal, 24 at high, and 5 at excessive levels of iodine nutrition. Thus, it is imperative to weigh the benefits and risks of intensifying USI further. The WHO review places India in the category of "adequate" iodine nutrition, but in 2005 the Government of India promulgated a universal ban on sale of non-iodized salt, calling iodine deficiency disorders (IDDs) a major public health problem. This article attempts to understand these contradictions and weigh the benefits and costs of USI. Based on a review of studies since the 1920s, the authors reconstruct the evolution of IDD control in India. Conceptual and methodological limitations challenge the evidence base and rationale of stricter implementation of USI now. Finding evidence for its negative impact, the authors recommend a reexamination of the USI strategy and propose a safer, people-centered, ecosocial epidemiological approach rather than a universal legal ban.