ABSTRACT
INTRODUCTION: The goal of this study was to examine the fatty acid (FA) composition of the total plasma lipids of the native inhabitants of the Russian European North, taking into consideration the differences in lifestyles and nutritional habits as well as the interrelationship between the plasma FA profile and nutrition. METHODS: In total, 78 native residents of the Russian European North (61 men and 17 women) from two regions of Komi Republic of Northern Russia (Izhma settlement and city Syktyvkar), aged 25-45 years, were included in this study. The Izhma group consisted of reindeer herders (17 men and 17 women). The comparison group (44 men) consisted of citizens of Syktyvkar. Venous blood plasma after overnight fasting was used for analysis of glucose, cholesterol, triglycerides, vitamins and total FA composition. A modified questionnaire 'Seafood and the health of the people of the North' was used for the assessment of nutrition. RESULTS: The levels of total FAs in the blood plasma of Indigenous inhabitants of Russian European North were at the lower border of the reference range. In the Izhma group, levels of n-3 eicosapentaenoic acid (EPA) (1.3/0.9-1.8; p<0.001) and docosahexaenoic acid (DHA) (2.2/1.5-2.8; p=0.025), n-7 palmitoleic FA (2.3/1.9-2.5; p<0.001) were higher than in the Syktyvkar group. At the same time, levels of n-6 linoleic acid (32.1/29.2-35.5; p=0.003) were significantly lower in the male reindeer herders of Izhma. Comparison of the nutritional habits of both groups revealed larger consumption of fish, meat and reindeer fat (p<0.001), eggs (p=0.004), high-carbohydrate products (white bread (p=0.033) and macaroni (p<0.001)) by reindeer herders of Izhma. The participants in the urban group demonstrated higher consumption of fruits (p<0.001), butter (p=0.013), cultured milk foods (p=0.010) and vegetables (p=0.009). CONCLUSIONS: The results of the study showed more beneficial n-6/n-3 FA ratios in reindeer herders of Russian European North than in urban inhabitants. Higher plasma polyunsaturated n-3 FA (EPA, DHA) levels in reindeer herders who had more fish in their diet were demonstrated. In addition, inland reindeer herders showed higher palmitoleic acid levels and lower linoleic acid levels in blood total lipids than urban inhabitants. The nutritional features and environmental conditions were assumed to have the greatest effects on plasma FA profiles and lipid metabolism in the Indigenous inhabitants of Russian European North.
