Características sociodemográficas, nutricionais e aspectos da diversidade bacteriana na microbiota intestinal de indivíduos com diferentes hábitos alimentares

Abstract

The human gut microbiota (MIH) has a high density and diversity of microorganisms, performing important functions, such as energy and nutrient supply and immune modulation, and its imbalance is related to several pathologies. MIH regulation is closely related to eating habits, which could be used to modulate the relationship between host and MIH, representing a possible path for therapeutic interventions to prevent and control diseases. Therefore, the present study aimed to evaluate the structure of bacterial communities in healthy individuals with different eating habits and to correlate with their nutritional characteristics. Strict vegetarian volunteers (n=19), lacto-ovo-vegetarians (n=20) and omnivores (n=19) were submitted to nutritional and anthropometric assessment and fecal samples were collected and analyzed by cultivation in selective culture mediaand real-time PCR. Cultures with viable bacterial growth were submitted to CFU counting and morphotype evaluation. In the real-time PCR analysis, the Firmicutes, Bacteroidetes, γ-Proteobacteria and Lactobacillus bacterial groups were evaluated. The diet of strict vegetarians exhibited higher consumption of carbohydrates and fiber and lower consumption of proteins and lipids. The high consumption of animal-derived proteins and lipids seems to be related to the increased abundance of potentially pathogenic Gram-negative bacteria in MIH. A qualitative grouping by similarity of these volunteers was not possible, which suggests that the different eating habits, in general, would not be enough to cause qualitative differences in the composition of the MIH. However, a bacterial core in common to the three groups was formed, which could be related to the consumption of fresh or minimally processed vegetables. Therefore, different macronutrient intake, as well as types and forms of food consumption, play a major role in microorganisms abundance in MIH.