Physical activity enhances the improvement of body mass index and metabolism by inulin: a multicenter randomized placebo-controlled trial performed in obese individuals

Abstract

Background Dietary interventions targeting the gut microbiota have been proposed as innovative strategies to improve obesity-associated metabolic disorders. Increasing physical activity (PA) is considered as a key behavioral change for improving health. We have tested the hypothesis that changing the PA status during a nutritional intervention based on prebiotic supplementation can alter or even change the metabolic response to the prebiotic. We confirm in obese subjects and in high-fat diet fed mice that performing PA in parallel to a prebiotic supplementation is necessary to observe metabolic improvements upon inulin. Methods A randomized, single-blinded, multicentric, placebo-controlled trial was conducted in obese participants who received 16 g/day native inulin versus maltodextrin, coupled to dietary advice to consume inulin-rich versus -poor vegetables for 3 months, respectively, in addition to dietary caloric restriction. Primary outcomes concern the changes on the gut microbiota composition, and secondary outcomes are related to the measures of anthropometric and metabolic parameters, as well as the evaluation of PA. Among the 106 patients who completed the study, 61 patients filled a questionnaire for PA before and after intervention (placebo: n = 31, prebiotic: n = 30). Except the dietitian (who provided dietary advices and recipes book), all participants and research staff were blinded to the treatments and no advices related to PA were given to participants in order to change their habits. In parallel, a preclinical study was designed combining both inulin supplementation and voluntary exercise in a model of diet-induced obesity in mice. Results Obese subjects who increased PA during a 3 months intervention with inulin-enriched diet exhibited several clinical improvements such as reduced BMI (− 1.6 kg/m2), decreased liver enzymes and plasma cholesterol, and improved glucose tolerance. Interestingly, the regulations of Bifidobacterium, Dialister, and Catenibacterium genera by inulin were only significant when participants exercised more. In obese mice, we highlighted a greater gut fermentation of inulin and improved glucose homeostasis when PA is combined with prebiotics. Conclusion We conclude that PA level is an important determinant of the success of a dietary intervention targeting the gut microbiota. Trial registration ClinicalTrials.gov, NCT03852069 (February 22, 2019 retrospectively registered).

Dietary regulation in health and disease

“… 248 , 249 In similar, daily high-inulin supplementation combined with excise are able to reduce cholesterol level in plasma and liver, improve glucose tolerance and lead to weight loss through augmentation of inulin-degrading bacteria in gut. 250 In contrast, a CNOT6L inhibitor elevates hepatokine FGF21 and growth differentiation factor 15 (GDF15) levels by stabilizing their mRNAs and resulted in a remarkable improvement of overnutrition-induced metabolic syndrome. 251 …”

Intervention time modified the effect of inulin on high‐fat diet‐induced obesity and gut microbial disorders

“…In experimental animals as well as humans, inulin supplementation has been shown to improve gut ecosystem and reduce the risk of obesity and other metabolic diseases (Li et al., 2021; Reynolds et al., 2019b; Rodriguez, Neyrinck, et al., 2022). This study explored the effect of intervention time of inulin on HFD‐induced obesity in mice.…”

The Related Metabolic Diseases and Treatments of Obesity

“…All these factors are associated with obesity-induced comorbidities. Many factors can cause an alteration of the gut microbiota profile to impact obesity, including diet [ 128 ], BS [ 109 ], physical activity [ 129 , 130 ], probiotics (e.g., Bifidobacterium and Lacticaseibacillus ) [ 131 , 132 ], prebiotics, and synbiotics (containing both probiotic and prebiotic components).…”