Gut Microbiota during Dietary Restrictions: New Insights in Non-Communicable Diseases

Abstract

In recent decades, there has been a growing interest in dietary restrictions for their promising effects on longevity and health span. Indeed, these strategies are supposed to delay the onset and burden of non-communicable diseases (NCDs) such as obesity, diabetes, cancer and neurological and gastrointestinal inflammatory diseases. At the same time, the gut microbiota has been shown to play a crucial role in NCDs since it is actively involved in maintaining gut homeostasis through its impact on nutrients metabolism, gut barrier, and immune system. There is evidence that dietary restrictions could slow down age-related changes in the types and numbers of gut bacteria, which may counteract gut dysbiosis. The beneficial effects on gut microbiota may positively influence host metabolism, gut barrier permeability, and brain functions, and subsequently, postpone the onset of NCDs prolonging the health span. These new insights could lead to the development of novel strategies for modulating gut microbiota with the end goal of treating/preventing NCDs. This review provides an overview of animal and human studies focusing on gut microbiota variations during different types of dietary restriction, in order to highlight the close relationship between gut microbiota balance and the host’s health benefits induced by these nutritional regimens.

Nutritional Interventions Targeting Gut Microbiota during Cancer Therapies

“…Dietary restrictions include: (i) caloric restriction (CR) (defined by a 20–50% reduction in energy without malnutrition or reduction in essential nutrients occurring), but also (ii) time-restricted feeding (TRF) (which provides food intake in a 4- to 12-h time window), (iii) intermittent fasting (IF) (which provides an alternation of 24-h fasting with a 24-h ad libitum eating period), or (iv) fasting-mimicking diet (FMD) (a reduction of caloric intake for five consecutive days, through a low-caloric vegetable-based diet, before returning to normal eating cycles, once a month) [ 105 ]. In recent decades, there has been growing interest in dietary restrictions for their role in delaying the onset and burden of cancers, as well as many other non-communicable diseases [ 106 , 107 ].…”

Long-Term Effects of Bariatric Surgery on Gut Microbiota Composition and Faecal Metabolome Related to Obesity Remission

“…Additionally, microbial metabolism of dietary nutrients may produce potential harmful substances related to the instauration of the low-grade inflammatory state of obesity [ 11 ]. Weight loss by means of dietary interventions modify gut microbiota, counteracting the extensively reported elevated Firmicutes/Bacteroidetes ratio in obesity and increasing beneficial Verrucomicrobia phylum [ 12 ], but also promoting functional changes in the microbiota and altering its derived metabolites [ 13 , 14 ]. Likewise, bariatric surgery could drive a shift of the metabolic capacity of the gut microbiota towards a lean-like phenotype, both from a composition and from a functional point of view, related to the good outcomes of the procedure.…”

Efficacy of therapeutic fasting and plant-based diet in patients with rheumatoid arthritis (NutriFast): study protocol for a randomised controlled clinical trial

“… 11 30 This also applies to caloric restriction or fasting, an element which can be implemented in different types of diets. 31 32 …”