Farinaceous and starchy foods in the diet of the indigenous people of the high-latitude and Arctic regions of Russia: tradition and modernity

The object of the study is the indigenous population of the North and the Arctic of the Russian Federation. The subject of the study is changes in nutrition during transition from the traditional to modernized lifestyle. The purpose of the study is to consider the risk to the health of the northerners in the quantitative and qualitative changes in the consumption of flour and starch-containing products. The consumption of bread products and starch by the population of the northern regions of the Russian Federation in the 19th – 20th centuries and in the 2010s – 2020s was estimated. Estimates of the frequencies of the amylase genes AMY1, AMY2B, AMY2A in the populations that differ in geographic localization and type of management are systemized. In the 20th century, per-capita consumption of bread in Russia decreased from 700 to 260 g/day, among the indeginous northerners — from 300 to 250 g/day. The inclusion of pasta products and potato in the diet of the northerners changed the volume and structure of the consumed carbohydrate foods. The intake of high glycemic load starch increased from 100 to 250 g/day. Replacing the dried crusts with pasta and potato meals eased mastication of food, thus inducing a reflectory rise in serum glucose at ingestion and increasing the risk of developing chronic carbohydrate metabolism disorders. High-latitude populations are distinct in the prevalence of the genotypes that determine low activity of the polysaccharidase enzymes necessary for starch digestion. The ample production of amylase and less prominent blood glucose upswing in response to the consumption of starchy foods are determined by the number of successive copies of the amylase genes on the AMY locus. For the AMY1 gene, a negative correlation was found between the gene copy number and the geographical latitude of the population area (rSp = -0.19), for the AMY2A gene rSp = -0.33 (p < 0.001 in both cases). In addition, in the Arctic groups there is a high frequency of deletions of the AMY2A gene, which also lead to insufficient synthesis of pancreatic amylase. In the European populations, AMY2A deletions occur in 10–11 %; among the Khanty, Mansi, and Selkups — in 28 %; among the indigenous population of Chukotka — in 52 %. Changes in the “Arctic diet” in the 20th century led to a sharp increase in the starch consumption. With the traditional way of life, the northerners did not form adaptations to the nutrient intake of large volumes of starchy foods. In modern conditions, accumulation of nutritional, physiological and genetic factors increases the risk of metabolic disorders related to the consumption of high-starch food.