Effect of the ingestion of vegetable oils associated with energy-restricted normofat diet on intestinal microbiota and permeability in overweight women.

Previous studies suggest that the type of dietary fatty acid may modulate the intestinal bacterial ecosystem. However, this effect is still inconclusive. Thus, the aim of this study was to investigate the effect of the intake of vegetable oils rich in different types of fatty acids, associated with energy-restricted normofat diets, on the composition of intestinal microbiota and permeability, on LPS concentrations, and fecal short chain fatty acids and pH. This was a 9 consecutive weeks (±5 days), randomized, parallel, double-blind clinical trial. Overweight women received daily breakfast containing 25 mL of one of the test oils: soybean oil (n = 17), extra virgin olive oil (n = 19) or coconut oil (n = 16). Blood, fecal and urine samples were collected on the first and last day of the experiment for the analysis of the variables of interest. The consumption of the three oils did not affect the diversity and relative abundance of intestinal bacteria. We observed an increase in bacterial richness estimated by the Chao 1 index, and a reduction in the concentration of isovaleric fatty acid in the group that ingested soybean oil. Paracellular and transcellular permeability increased after the ingestion of extra virgin olive oil and coconut oil. However, LPS concentrations remained unchanged. The intake of different types of fatty acids associated with the energy-restricted normofat diet modestly affected the intestinal microbiota and permeability, without resulting in metabolic endotoxemia in overweight women.

Dysbiosis and metabolic endotoxemia induced by high-fat diet.

INTRODUCTION: diet plays a decisive role in the prevention and treatment of diseases such as obesity, diabetes, allergies and inflammatory diseases. In addition to this, there are numerous investigations about the role of the microbiota in the genesis of metabolic diseases, especially obesity and its comorbidities. OBJECTIVE: the aim of this review is to discuss the influence of high-fat diets on dysbiosis and metabolic endotoxemia. RESULTS AND CONCLUSION: the intestinal microbial ecosystem has been shown to be essential in the performance of functions in the host organism, however, several factors can lead to an imbalance in the homeostasis of the microbiota, known as dysbiosis. High-fat diets are associated with a reduction in intestinal bacterial diversity, changes in membrane integrity, inducing increased permeability and increased lipopolysaccharide (LPS) translocation, changes in the immune system, and generation of low-intensity systemic inflammation. The installed endotoxemia can be considered as a causal factor of subclinical inflammation related to several chronic diseases, and as a result of this, it is essential to know the real impact of hyperlipidic diets on the intestinal microbiota. Thus, it becomes essential to identify dietary strategies that can minimize the inflammatory effects generated from changes in the intestinal microbiota.