AUTHOR=Aldubayan Mona Adnan , Mao Xiaotian , Laursen Martin Frederik , Pigsborg Kristina , Christensen Lars H. , Roager Henrik M. , Nielsen Dennis S. , Hjorth Mads Fiil , Magkos Faidon 

TITLE=Supplementation with inulin-type fructans affects gut microbiota and attenuates some of the cardiometabolic benefits of a plant-based diet in individuals with overweight or obesity

JOURNAL=Frontiers in Nutrition

VOLUME=10

YEAR=2023

URL=https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2023.1108088

DOI=10.3389/fnut.2023.1108088

ISSN=2296-861X

ABSTRACT=<sec><title>Background</title><p>The gut microbiota has emerged as a potential therapeutic target to improve the management of obesity and its comorbidities.</p></sec><sec><title>Objective</title><p>We investigated the impact of a high fiber (∼38 g/d) plant-based diet, consumed <italic>ad libitum</italic>, with or without added inulin-type fructans (ITF), on the gut microbiota composition and cardiometabolic outcomes in subjects with obesity. We also tested if baseline <italic>Prevotella/Bacteroides</italic> (P/B) ratio predicts weight loss outcomes.</p></sec><sec><title>Methods</title><p>This is a secondary exploratory analysis from the PREVENTOMICS study, in which 100 subjects (82 completers) aged 18–65 years with body mass index 27–40 kg/m<sup>2</sup> were randomized to 10 weeks of double-blinded treatment with a personalized or a generic plant-based diet. Changes from baseline to end-of-trial in gut microbiota composition (16S rRNA gene amplicon sequencing), body composition, cardiometabolic health and inflammatory markers were evaluated in the whole cohort (<italic>n</italic> = 82), and also compared in the subgroup of subjects who were supplemented with an additional 20 g/d ITF-prebiotics (<italic>n</italic> = 21) or their controls (<italic>n</italic> = 22).</p></sec><sec><title>Results</title><p>In response to the plant-based diet, all subjects lost weight (−3.2 [95% CI –3.9, −2.5] kg) and experienced significant improvements in body composition and cardiometabolic health indices. Addition of ITF to the plant-based diet reduced microbial diversity (Shannon index) and selectively increased <italic>Bifidobacterium</italic> and <italic>Faecalibacterium</italic> (<italic>q</italic> &lt; 0.05). The change in the latter was significantly associated with higher values of insulin and HOMA-IR and lower HDL cholesterol. In addition, the LDL:HDL ratio and the concentrations of IL-10, MCP-1 and TNFα were significantly elevated in the ITF-subgroup. There was no relationship between baseline P/B ratio and changes in body weight (<italic>r</italic> = −0.07, <italic>p</italic> = 0.53).</p></sec><sec><title>Conclusion</title><p>A plant-based diet consumed <italic>ad libitum</italic> modestly decreases body weight and has multiple health benefits in individuals with obesity. Addition of ITF-prebiotics on top this naturally fiber-rich background selectively changes gut microbiota composition and attenuates some of the realized cardiometabolic benefits.</p></sec><sec><title>Clinical trial registration</title><p>[<ext-link xlink:href="https://clinicaltrials.gov/ct2/show/NCT04590989" ext-link-type="uri" xmlns:xlink="http://www.w3.org/1999/xlink">https://clinicaltrials.gov/ct2/show/NCT04590989</ext-link>], identifier [NCT04590989].</p></sec>