| This study examined the health consequences of economic development in the Yakut (Sakha), a high-latitude indigenous pastoral population from northeastern Siberia. The three main objectives were: (1) to investigate metabolic adaptation; (2) to explore health and energy balance within the context of economic modernization; and (3) to examine the intersection of biological adaptation and lifestyle change.;Research was conducted in the Sakha Republic of Russia. Energetic (basal metabolic rate [BMR] and total energy expenditure [TEE]), anthropometric (body size and composition), and blood pressure data were obtained from Yakut adults. Extensive information on lifestyle, socioeconomic status, and diet was assessed by questionnaire. Yakut men and women had significantly elevated BMRs compared to reference norms, which were not attributable to body composition, diet, or anxiety. Further, no significant relationships were documented between lifestyle variables and BMR, suggesting a role for genetic and/or developmental factors. TEE and physical activity level (PAL; TEE/BMR) were measured over a 10-day period using the doubly labeled water (DLW) technique. Physical activity levels among the Yakut were relatively low compared to other subsistence populations, especially among women, and similar to individuals in industrialized nations. Individuals who participated in more subsistence activities and consumed fewer market foods had significantly higher activity levels.;Obesity has emerged as a health problem for both Yakut men and women. However, there were significant sex differences in the relationship between lifestyle and body composition; affluence was positively associated with obesity among men, while the reverse was true for women. Hypertension was identified as a major health concern, especially among men. In both sexes, elevated blood pressure was associated with greater age and adiposity, and relatively lower income; among men it was also associated with prolonged television viewing. Blood pressure was also positively associated with BMR, independent of body size and composition.;Overall, this study demonstrated that economic modernization exerted profound and variable effects on Yakut health, which were shaped by both lifestyle factors and by physiological adaptation to the circumpolar environment. These findings underscore the importance of examining how human adaptability influences health changes in response to economic modernization. |
