Relationship between salt consumption and iodine intake in a pediatric population

Abstract

Purpose The World Health Organization recommends reduction of salt intake to < 5 g/day and the use of iodized salt to prevent iodine deficiency states. A high prevalence of excess salt consumption and an inadequate iodine intake has been previously shown in an Italian pediatric population. It was appropriate, therefore, to analyse in the same population the relationship occurring between salt consumption and iodine intake. Methods The study population was made of 1270 children and adolescents. Estimates of salt consumption and iodine intake were obtained by measuring 24 h urinary sodium and iodine excretion. Results The iodine intake increased gradually across quartiles of salt consumption independently of sex, age and body weight (p < 0.001). Median iodine intake met the European Food Safety Authority adequacy level only in teenagers in the highest quartile of salt consumption (salt intake > 10.2 g/day). We estimated that approximately 65–73% of the total iodine intake was derived from food and 27–35% from iodized salt and that iodized salt made actually only 20% of the total salt intake. Conclusion In this pediatric population, in face of an elevated average salt consumption, the use of iodized salt was still insufficient to ensure an adequate iodine intake, in particular among teenagers. In the perspective of a progressive reduction of total salt intake, the health institutions should continue to support iodoprophylaxis, in the context of the national strategies for salt reduction. In order for these policies to be successful, in addition to educational campaigns, it is needed that the prescriptions contained in the current legislation on iodoprophylaxis are made compelling through specific enforcement measures for all the involved stakeholders.

Iodine Intake from Food and Iodized Salt as Related to Dietary Salt Consumption in the Italian Adult General Population

“…Similar to the present study, also in the children and adolescent population an adequate iodine intake was reached only at the cost of a very high sodium intake with respect to WHO recommendation [ 20 ]. In the paediatric population, it was estimated that 72% of iodine was provided by food in children and in female adolescents, with a slightly lower figure (65%) in male adolescents [ 20 ]. In the present study, the provision of iodine from food for the whole population amounted to about 57%.…”

“…These results are in line with those recently reported for a national Italian paediatric population sample which was examined in the same period of the present survey. Both among children and adolescents [ 20 ] and male and female adults here reported the proportion of iodized salt out of total salt intake varied from a minimum of 16% to a maximum of 29% in different sex and age categories. Similar to the present study, also in the children and adolescent population an adequate iodine intake was reached only at the cost of a very high sodium intake with respect to WHO recommendation [ 20 ].…”

“…Both among children and adolescents [ 20 ] and male and female adults here reported the proportion of iodized salt out of total salt intake varied from a minimum of 16% to a maximum of 29% in different sex and age categories. Similar to the present study, also in the children and adolescent population an adequate iodine intake was reached only at the cost of a very high sodium intake with respect to WHO recommendation [ 20 ]. In the paediatric population, it was estimated that 72% of iodine was provided by food in children and in female adolescents, with a slightly lower figure (65%) in male adolescents [ 20 ].…”

“…The estimation of the total iodine provision by food and by iodized salt was made considering a 30% iodine loss occurring through cooking and stocking [ 20 ]. The amount of iodine deriving from the use of salt was estimated by subtracting the iodine provided by food from the total iodine uptake.…”

Salt reduction and iodine intake in Italy

“…In the perspective of a progressive salt reduction in Italy, some authors have suggested a wider use of iodized salt in food industry and a possible increase in iodine concentration of salt to maintain and guarantee the effectiveness of iodine prophylaxis program [13]. In Italy, as in other parts of the world, eating habits are changing because people more often consume food produced or cooked outside the households so that processed foods represent the main source of salt in Western diet (70-80% of total salt consumed).…”