**Abstract**

Exposure to environmental toxins in water, soil and air are increasing with health effects, mainly in older ages and physiological states (childhood and pregnancy). The role of the microbiota has been widely studied with effects on the maintenance of health but this is only possible with a diet that promotes it. The traditional Mexican diet is rich in fiber, which has prebiotic effects and has found a higher excretion of arsenic and fluoride in adolescents who maintained a diet high in fiber derived from traditional foods. After several descriptive studies in the state of Guanajuato, since 2004, first with arsenic in drinking water in population of several communities, in 2015, it is achieved through an intervention study with a supplementation of several vitamins and minerals in population adolescent, a greater urinary arsenic and fluoride excretion, as well as a greater consumption of traditional foods such as beans, bananas, orange and quelites. Food is key to maintain a function of the microbiota, so its review and study should be encouraged.

**Keywords:** microbiome, traditional Mexican diet, soluble fiber, arsenic, fluoride
