Intergroup variability of body circumferences and subcutaneous fat deposition in young men of different ethnic groups

Introduction. This study is devoted to intergroup variability of body circumferences, degree and to-pography of subcutaneous fat deposition in samples of young men of different ethnic backgrounds. Materials and Methods. We used anthropometric survey data from Russian men from various regions of Russia, indigenous Altaians and Tuvans from the Altai and Tyva Republics measured in the period from 2015 to 2019. Anthropometric measurements were performed according to standard methods of the Re-search Institute and the Museum of Anthropology of Moscow State University using GPM (DKSH, Switzer-land) and Holtain (Holtain Ltd, UK) anthropometric instruments. Body composition was assessed by bioelec-trical impedance analysis using ABC-02 Medass (Medass, Russia). We analyzed body circumferences, the value of fat and skin folds in various points of the body, bioimpedance measurements, and central fat dep-osition indices. Mathematical processing of the data was performed using the standard Statistica 10 soft-ware package. Discriminant (canonical) analysis was performed to study the topography of subcutaneous fat deposition. The materials have been collected from the population of these territories randomly and anonymously, according to the rules of bioethics and protocols of informed consent. Results. A comparative analysis of the main statistical parameters in three ethnic samples of men showed no significant differences in body mass index, the amount of fat mass, and most circumferences measurements. Intergroup variability was clearly evident in the thickness of fat and skin folds, in the index of central obesity (waist-to-height ratio), in the waist-to-hip ratio, and in the body adiposity index (BAI). In Tuvans, the value of fat and skin folds in the abdominal area and on the inner surface of the shoulder is significantly greater than in Russians and Altaians; in Russians, the mean values of all fat deposition indices are significantly lower than in Altaians and Tuvans. The canonical analysis of the set of body circumferences and fat and skin folds showed the predominant development of waist and shoulder circumferences and subcutaneous fat deposition on the body in Altaians and Tuvans as compared to Russians. Conclusions. The nature of intergroup variability indicates a predisposition of the Altaians and Tu-vans to the central type of fat deposition, which can be regarded as a result of adaptation under environ-mental stress in most Mongoloid populations of Southern Siberia.