[Status and selenium intake as related to the thyroid gland in the population of Znojmo]

In a group of 360 people aged 6-65 years of both sexes from the Znojmo area the author investigated the selenium status and intake by serum analyses (246 cases), urine analyses (356 cases) and hair analyses (28 analyses in middle-aged men). By correlation analysis the author investigated the relationship of selenium and metabolic and peripheral thyroid parameters. From the low selenium concentration in all investigated materials (42 micrograms Se/l serum, 8.2 micrograms Se/urine, 7.2 micrograms Se/g creatinine in urine and 0.23 microgram Se/g hair) the author concludes that there is selenium deficiency in the investigated population, the primary cause being a low dietary selenium intake (average adult intake 17 to 25 micrograms Se/day). From significant, though loose correlations between selenium concentrations and thyroid parameters (size, texture, number of nodes), serum concentrations of thyroid hormones (and their ratios resp.), as well peripheral parameters of hormone actions (Achilles tendon reflex, pulse rate or anthropometric variables) the conclusion is drawn that the selenium deficiency is so marked that it interferes in the investigated population with the regulation of the organism by thyroid hormones. This effect may be caused by changes of hormone formation in the thyroid gland due to the concentration of Se-dependent peroxidase, but in particular changes of their metabolism in the circulation and periphery, as selenium participates in the active centre of deiodase I in the formation of metabolically active triiodothyronine, and selenium deficiency has an impact also on deiodase II activity in some specialized tissues.