Double fortified salt at crossroads

Abstract

Iron Deficiency Anemia (IDA) and Iodine Deficiency Disorders (IDD) are the major public health problems often co-existing in many regions in our country. National Institute of Nutrition (NIN) has promoted the technology of double fortification of common salt with iodine and iron as a strategy to control both deficiencies under food-based approaches. Two other formulations of double fortified salt (DFS) have been subsequently developed by other agencies. NIN formulation & Nutrisalt have a stabilizer/promoter to maintain the stability of iodine in the presence of iron. The Micronutrient Initiative (MI) formulation uses physical separation of iodine by microencapsulation. NIN carried out extensive studies on stability, bioavailability, acceptability, safety and impact (including in community) of DFS. Feasibility both at factory level production and community level implementation have been worked out. MI salt had also undergone stability, acceptability and impact studies. No data is reported on the stability of Nutrisalt except that good stability is claimed in the available reports. In principle, the strategy of double fortification of salt with iron and iodine is sound with uniformly good impact on urinary iodine excretion and prevention of anemia. However, striking increments in hemoglobin (Hb) were not readily demonstrated since the intended purpose of DFS was only to provide iron at maintenance level and not therapeutic level. Complexities in the experimental designs, confounding variables and quality of the ingredients in salts also contributed to difficulties in interpretation of Hb status in studies involving DFS. Along with improvements contemplated in formulation to enhance the stability and bioavailibility, DFS should be able to fulfil the promise and realise its potential in reducing iron and iodine deficiency amongst our poor population in the next few years.