Vitamin D Status in Different Age Groups of the Population of Khanty-Mansiysk

Taking into account the wide range of physiological effects of vitamin D on the human body and the dependence of its synthesis in the skin on insolation, it is of undoubted interest to study vitamin D status in various population groups in the Russian North. The purpose of this article was to investigate vitamin D levels in the blood serum of people of various age groups living in Khanty-Mansiysk, Russia. Materials and methods. The research was conducted at the clinical and biochemical laboratory of the district clinical hospital in KhantyMansiysk during the autumn–winter–spring periods of 2021, 2022 and 2023. The study involved 3120 residents of Khanty-Mansiysk (61°N), including 493 children and adolescents, 798 young people, 887 middle-aged and 942 older adults. Their serum 25(OH)D levels were determined using enzyme immunoassay; the arithmetic mean (M), standard deviation and median (Me) as well as minimum and maximum values were calculated. The obtained data were compared with the reference values. Results. Vitamin D deficiency was established in all studied groups of the population of Khanty-Mansiysk regardless of their sex, being the most pronounced in children and adolescents due to intensive growth (M = 23.5 ng/ml, Me = 22.1 ng/ml) and in older adults (M = 22.5 ng/ml, Me = 21.7 ng/ml) due to significantly declined synthesis of cholecalciferol in the skin when exposed to ultraviolet radiation. There is a need for a widespread implementation of educational programmes informing healthcare workers and the population about the importance of vitamin D for metabolism, the prevalence of conditions related to vitamin D deficiency, and the measures for hypovitaminosis D prevention, such as consuming vitamin D-rich foods and taking vitamin D supplements in combination with longer sun exposure time in the south of Russia and abroad.