To estimate the status of selenium in seniors of the South Bohemia region, Czech Republic, 481 serum samples from seniors
living in 17 Asylum Houses for seniors in the age between 60 and 99 years were obtained. Samples were analyzed by instrumental
neutron activation analysis with concurrent analysis of 4 reference materials for quality assurance. Average concentration
of serum Se, arithmetic means in individual Asylum Houses, frequency distribution of serum Se concentrations as well as five
years running monitoring of serum Se concentrations of one group of seniors proved selenium deficiency of the elderly population
of the region South Bohemia.