Diet-induced gut dysbiosis and leaky gut syndrome are significant factors in the development of metabolic diseases such as obesity. This review explores the relationship between diet and gut microbiota, highlighting how dietary factors influence gut health and the gut-liver and gut-brain axes. High-fat diets (HFDs) and high-carbohydrate diets (HCDs) disrupt the intestinal barrier, leading to increased intestinal permeability and the translocation of endotoxins like lipopolysaccharides (LPSs), which can cause metabolic endotoxemia and alter the gut microbiome. These changes are associated with inflammation, metabolic disorders, and conditions such as non-alcoholic fatty liver disease (NAFLD) and obesity. The gut microbiota plays a crucial role in maintaining intestinal barrier function, and imbalances in gut microbiota can lead to dysbiosis, which is linked to various diseases. Artificial sweeteners may also affect gut microbiota composition, potentially contributing to metabolic disorders. The review emphasizes the importance of understanding the complex interactions between diet, gut microbiota, and the gut-liver and gut-brain axes to develop effective interventions for improving gut health and preventing metabolic diseases. Further research is needed to fully elucidate these mechanisms and their implications for human health.Diet-induced gut dysbiosis and leaky gut syndrome are significant factors in the development of metabolic diseases such as obesity. This review explores the relationship between diet and gut microbiota, highlighting how dietary factors influence gut health and the gut-liver and gut-brain axes. High-fat diets (HFDs) and high-carbohydrate diets (HCDs) disrupt the intestinal barrier, leading to increased intestinal permeability and the translocation of endotoxins like lipopolysaccharides (LPSs), which can cause metabolic endotoxemia and alter the gut microbiome. These changes are associated with inflammation, metabolic disorders, and conditions such as non-alcoholic fatty liver disease (NAFLD) and obesity. The gut microbiota plays a crucial role in maintaining intestinal barrier function, and imbalances in gut microbiota can lead to dysbiosis, which is linked to various diseases. Artificial sweeteners may also affect gut microbiota composition, potentially contributing to metabolic disorders. The review emphasizes the importance of understanding the complex interactions between diet, gut microbiota, and the gut-liver and gut-brain axes to develop effective interventions for improving gut health and preventing metabolic diseases. Further research is needed to fully elucidate these mechanisms and their implications for human health.