Gut microbiome, lipopolysaccharide and butyrate responses to cereal fibre-based interventions in overweight and obese adults: a pilot study

Cereal fibre modulates the gut microbiome and improves metabolic health. An understanding of any potential interaction between these effects is not yet clear, particularly, if there is a different effect with different cereal fibre types. This research aimed to measure changes to microbiome composition, butyrate and lipopolysaccharide levels in response to intake of specific cereal fibres. Overweight and obese healthy adults were provided with 45 g of four different cereal fibre interventions for three weeks each with three weeks washout between interventions in a randomised crossover design. Dietary intake was measured during each intervention period using a 3 day food record. Microbiome composition, serum butyrate and LPS levels were measured before and after each intervention. In ten subjects that completed all cereals, alpha diversity was reduced after moderate beta glucan intakes. Minor significant changes to microbiome composition were evident with different fibre types including increased Rhodospirillales post moderate beta glucan intake compared to only 2 percent post sorghum intake. No significant outcomes associated with beta-diversity, butyrate production or LPS levels were noted. This research provides evidence for different responses in microbiome composition with different cereal fibre types in overweight and obese adults and highlights the inter-individual responsiveness to diet. Further research is required before conclusions can be drawn regarding mechanistic links between cereal fibre, microbiome characteristics and metabolic risk.