Iodination of foodstuffs is one basic trend in prevention of iodine deficit and diseases caused by it. The production of iodine salt is rather expensive, and hence, another highly prevalent foodstuff was chosen as "iodine carrier": bread. Bread is traditional food in Russia and its consumption is stable throughout the year. Bread baking is centralized in the majority of regions of our country. It is manufactured at rather large bakeries and delivered even to the most faraway regions. In order to solve the practical problems of baking iodinated bread, a pilot experiment was carried out in 1993-1995 in the Pavlovsky Posad district near Moscow (a region with moderate and slight iodine deficiency). The experiment was sponsored by the UNICEF (UN Childhood Foundation) and included development of the formula of bread iodination and assessment of this method of iodine prophylaxis. According to the proposed formula, 60 mg of potassium iodide is to be added per 100 g of flour; such a dose covers the daily requirement of an organism in iodine, provided 500 g of bread is consumed daily. The efficacy of iodinated bread was assessed from the time course of renal excretion of iodine and incidence of thyroid enlargement in 162 schoolchildren aged 7 to 14 at a boarding school in the town of Pavlovsky Posad, who were given 300 g of bread daily, and in 178 schoolchildren aged 9 to 11 living in the rural regions, eating about 100 g daily. After 3 months the median level of urinary iodine increased from 4.8 to 12.6 pg% in town and from 3.0 to 6.2 pg% in the country. After 9 months the levels of urinary excretion of iodine were the same, moreover, the incidence of thyroid enlargement decreased in both groups. Hence, the tasks of pilot experiment were fulfilled: a method for bread iodination has been developed and introduced at bakeries and its efficacy in normalization of iodine supply validated.