Diet impacts metabolic disease via gut microbiota alterations

This study investigates the effects of various plant-based dietary fibers on metabolic homeostasis in mice fed a high-fat diet (HFD). The research focuses on how these fibers influence gut microbiota and metabolites, which are crucial for understanding metabolic diseases. Mice were supplemented with five different types of fibers—pectin, β-glucan, wheat dextrin, resistant starch, and cellulose—over 18 weeks. The results indicated that only β-glucan significantly reduced body weight gain and adiposity while improving glucose tolerance compared to the cellulose control. This effect was linked to increased energy expenditure and physical activity in the β-glucan group. All fiber types altered the gut microbiota and the composition of cecal short-chain fatty acids, but only β-glucan supplementation led to higher levels of cecal butyrate. Additionally, all fibers modified the small-intestinal microbiota and portal bile acid composition. The findings suggest that β-glucan may be an effective dietary intervention for metabolic diseases, potentially through its ability to enhance energy expenditure and modify gut microbiota and bacterial metabolites. This research highlights the importance of specific dietary fibers in managing metabolic health and their differential effects on gut microbiota.