This interesting and well-balanced review examined how long-term and short-term changes in dietary fibre intake affect the microbiome and metabolome.
Greater microbial diversity is associated with long-term diets high in fruit/legume fibre, while beneficial Firmicutes decrease in diets high in fat/sugar and low in fibre.
Short-term diets based exclusively on animal products and those high in protein and low in fermentable carbohydrate/fibre are associated with increased abundance of Bacteroides and decreased Firmicutes. Long-term adherence to such diets may increase the risk of colonic disease. Fermentable prebiotic fibres that enhance Bifidobacteria or soluble fibres that block bacterial–epithelial adherence (contrabiotics) may serve as interventions to prevent intestinal inflammation.
In summary, the microbiome and metabolome appear to be influenced by fibre in both long-term and short-term dietary interventions. The mechanisms described in this paper may explain why long-term adherence to a diet rich in fruit and vegetable fibre is associated with a different microbiota in both humans and animals.
Simpson HL. & Campbell J. (2015) Review article: dietary fibre-microbiota interactions. Alimentary Pharmacology & Therapeutics 42(2), pp. 158-179. doi: 10.1111/apt.13248