Lipiodol, an iodinated oil preparation, is used in many regions of the world characterized by severe iodine defficiency. The aim of this research was to assess the efficacy of this preparation in regions with slight and medium iodine insufficiency. A single dose of lipidol containing 200 mg iodine was administered to children aged 7 to 14 living in a region with moderate iodine deficiency, 452 of these living in town and 335 in the country. According to volumetry, the incidence of thyroid enlargement varied from 43 to 61% for different age groups and was reliably higher (p <0.001)) in the rural residents. The median of renal excretion of iodine varied from 4.5 to 9.2 microg% in the urban schoolchildren and from 3.8 to 5.8 microg% in the rural ones. One week after lipidol administration this value was 38.8, two weeks postadministration it was 30 microg%, in 3 months it was 16, and in 9 months 11.3 microg%. The incidence of thyroid enlargement has appreciably decreased and varied from 18 to 47% in different age groups. Hence, a single intake of lipiodol containing 200 mg of iodine ensures normal iodine excretion with the urine for 9 months since the drug administration and essentially reduces the prevalence of goiter in regions with moderate iodine insufficiency. Lipidol may be recommended as an alternative method of iodine prophylaxis for regions with slight and moderate iodine deficiency

Regular (for 5 years) addition of salt iodinated with potassium iodinate to diets of children living in a region with moderate iodine deficiency normalized iodine content in the organism, decreased the incidence of goiter from 22.6 to 7.3% (according to ultrasonic data), and prevented an increase in the incidence of goiter during the prepubertal period. Evaluation of the size of goiter in screening examinations by palpation using О. V. Nikolaev’s classification leads to hyperdiagnosis (67%>), while palpation in combination with WHO classification results in hypodiagnosis of goiter (47%). Palpation of the thyroid with WHO classification is recommended as the main screening method; such a combination of methods results in a lower incidence of erroneous diagnoses (22%) than with Nikolaev's classification (56%). The level of serum TTH did not depend on iodine prophylaxis and was normal.