title: The multifactorial interplay of diet, the microbiome and appetite control: current knowledge and future challenges.
abstract: The recent availability of high-throughput nucleic acid sequencing technologies has rapidly advanced approaches to analysing the role of the gut microbiome in governance of human health, including gut health, and also metabolic, cardiovascular and mental health, inter alia. Recent scientific studies suggest that energy intake (EI) perturbations at the population level cannot account for the current obesity epidemic, and significant work is investigating the potential role of the microbiome, and in particular its metabolic products, notably SCFA, predominantly acetate, propionate and butyrate, the last of which is an energy source for the epithelium of the large intestine. The energy yield from dietary residues may be a significant factor influencing energy balance. This review posits that the contribution towards EI is governed by EI diet composition (not just fibre), the composition of the microbiome and by the levels of physical activity. Furthermore, we hypothesise that these factors do not exist in a steady state, but rather are dynamic, with both short- and medium-term effects on appetite regulation. We suggest that the existing modelling strategies for bacterial dynamics, specifically for growth in chemostat culture, are of utility in understanding the dynamic interplay of diet, activity and microbiomic organisation. Such approaches may be informative in optimising the application of dietary and microbial therapy to promote health.
authors.affiliation: Molecular Gastroenterology Research Group,Academic Unit of Surgical Oncology,Department of Oncology,University of Sheffield,Beech Hill Road,Sheffield S10 2RX,UK.
authors.forename: Bernard M
authors.initials: BM
authors.lastname: Corfe
authors.affiliation: Molecular Gastroenterology Research Group,Academic Unit of Surgical Oncology,Department of Oncology,University of Sheffield,Beech Hill Road,Sheffield S10 2RX,UK.
authors.forename: Charlotte J
authors.initials: CJ
authors.lastname: Harden
authors.affiliation: Organisms and Environment Division,Cardiff School of Biosciences, Cardiff University,Cardiff CF10 3AX,UK.
authors.forename: Matthew
authors.initials: M
authors.lastname: Bull
authors.affiliation: Cultech Ltd, Research Department,Port Talbot SA12 7BZ,UK.
authors.forename: Iveta
authors.initials: I
authors.lastname: Garaiova
mesh_terms: D001069:Appetite Regulation / Q000502:physiology*; D004032:Diet; D002149:Energy Intake; D004734:Energy Metabolism; D005232:Fatty Acids, Volatile / Q000096:biosynthesis / Q000378:metabolism; D000069196:Gastrointestinal Microbiome / Q000502:physiology*; D006801:Humans; D009765:Obesity / Q000378:metabolism* / Q000382:microbiology
chemical_list: D005232:Fatty Acids, Volatile
keywords: Appetite; EI energy intake; FFAR free fatty acid receptors; Fibre; GI gastrointestinal; IGN intestinal gluconeogenesis; Microbiome; Obesity; SCFA