Obesity is one of the major challenges in modern society. More than a third of the world's population suffers froms overweight. This phenotype affects the quality of life and is associated with cardiovascular diseases, diabetes, cancer and reproductive disorders. The population variability of allele frequencies of 26 single nucleotide polymorphisms, in association with obesity and body mass index, according to data from genome-wide association studies (GWASs) is discussed in this study. Genetic variability was analyzed in populations of Northern Eurasia and populations from the human genome diversity project (HGDP). The population samples are characterized by high genetic diversity that correlates with climatic and geographical parameters. The results of the test for searching for natural selection signals revealed a selection effect for rs1167827 of the HIP1 gene, rs7138803 and rs7164727 located in the intergenic region, rs7141420 of the NRXN3 gene, rs7498665 of the SH2B1 gene, and rs7903146 of the TCF7L2 gene.