Therefore, based on the high frequency of the FTO (rs9939609) TT genotype among the Wixárika and Nahuas, we suggest that this genotype could contribute to the Amerindian phenotype, characterized by a leaner body, lower adipose capacity, and lower risk of obesity/metabolic disturbances in an ancestral healthy cultural-food environment (Figure 3). This evidence concerns the gene FTO and obesity due to melanocortin 4 receptor deficiency.