A Low Glycemic Index Mediterranean Diet Combined with Aerobic Physical Activity Rearranges the Gut Microbiota Signature in NAFLD Patients

Abstract

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease, and its prevalence worldwide is increasing. Several studies support the pathophysiological role of the gut–liver axis, where specific signal pathways are finely tuned by intestinal microbiota both in the onset and progression of NAFLD. In the present study, we investigate the impact of different lifestyle interventions on the gut microbiota composition in 109 NAFLD patients randomly allocated to six lifestyle intervention groups: Low Glycemic Index Mediterranean Diet (LGIMD), aerobic activity program (ATFIS_1), combined activity program (ATFIS_2), LGIMD plus ATFIS_1 or ATFIS2 and Control Diet based on CREA-AN (INRAN). The relative abundances of microbial taxa at all taxonomic levels were explored in all the intervention groups and used to cluster samples based on a statistical approach, relying both on the discriminant analysis of principal components (DAPCs) and on a linear regression model. Our analyses reveal important differences when physical activity and the Mediterranean diet are merged as treatment and allow us to identify the most statistically significant taxa linked with liver protection. These findings agree with the decreased ‘controlled attenuation parameter’ (CAP) detected in the LGIMD-ATFIS_1 group, measured using FibroScan®. In conclusion, our study demonstrates the synergistic effect of lifestyle interventions (diet and/or physical activity programs) on the gut microbiota composition in NAFLD patients.

Lifestyle Intervention for Patients with Nonalcoholic Fatty Liver Disease: A Randomized Clinical Trial Based on the Theory of Planned Behavior

“…Studies performed in nutrition and physical activity demonstrated that changes in dietary compositions and physical activity rates lead to improved clinical features, namely, liver enzymes and ultrasound changes in NAFLD [ 42 – 45 ]. Results from the present study showed that educational sessions could improve the clinical conditions of patients with NAFLD by affecting their lifestyle.…”

“…Various studies were performed to demonstrate the effects of specific diet and physical activity on improving NAFLD [ 42 – 45 ], all of which addressed the desired intervention within the study period. Accordingly, it was cost-effective in one educational-supportive study, as the strength of the study.…”

Gut microbiota–mitochondrial inter-talk in non-alcoholic fatty liver disease

“…Consequently, different microbiota alterations were observed according to the different lifestyles. For example, the abundance of Ruminococcus, Oscillospiraceae-UCG002, Oscillospiraceae-UCG005, Dialister, Alistipes, and Eubacterium eligens showed an increasing trend, whereas that of Collinsella showed a decreasing trend in LGIMD-ATFIS_1 intervention, which was not found in other groups (106). In addition, a randomized controlled trial revealed that microbial diversity deteriorates with increased hepatic fat content, while exercise and diet may help maintain the diversity of the gut microbiota (107).…”

Nutraceuticals: Focus on Anti-Inflammatory, Anti-Cancer, Antioxidant Properties in Gastrointestinal Tract

“…Therefore, it is important to know not only the composition of foods, but also the effects that the different components produce in the body. It has been suggested that low-glycemic-load diets improve weight and fat mass loss compared to high-glycemic-load diets, and that reducing overall glycemic load is beneficial as an adjuvant in appetite regulation, in maintaining weight loss, and in controlling weight [ 76 , 77 , 78 ]. Even some important parameters of cardiovascular risk (such as triglycerides and HDL cholesterol) and the parameters of the “inflammatory state” of the organism, linked in multiple ways to the state of health, are favorably affected by the consumption of low-index foods and glycemic load.…”