The gut microbiota maintains a complex mutual interaction with different organs of the host. Whereas in normal conditions this natural community of trillions of microorganisms greatly contributes to the human health, gut dysbiosis is related with onset or worsening of diverse chronic systemic diseases. Thus, the reestablishment of gut microbiota homeostasis with consumption of prebiotics and probiotics may be a relevant strategy to prevent or attenuate several cardiovascular and metabolic complications. Among these functional foods, the synbiotic kefir, which is a fermented milk composed of a mixture of bacteria and yeasts, is currently the most used and has attracted the attention of health care professionals. The present review is focused on reports describing the feasibility of kefir consumption to provide benefits in cardiometabolic diseases, including hypertension, vascular endothelial dysfunction, dyslipidemia and insulin resistance. Interestingly, recent studies show that mechanisms of actions of kefir in cardiometabolic diseases include recruitment of endothelial progenitor cells, improvement of the balance vagal/sympathetic nervous system, diminution of excessive generation of reactive oxygen species, angiotensin converting enzyme inhibition, anti-inflammatory cytokines profile and alteration of the intestinal microbiota. These findings provide a better understanding about the mechanisms of the beneficial actions of kefir and motivate further investigations to determine whether the use of this synbiotic could also be translated into clinical improvements in cardiometabolic diseases.

The fact that millions of people worldwide suffer from Alzheimer’s disease (AD) or Parkinson’s disease (PD), the two most prevalent neurodegenerative diseases (NDs), has been a permanent challenge to science. New tools were developed over the past two decades and were immediately incorporated into routines in many laboratories, but the most valuable scientific contribution was the “waking up” of the gut microbiota. Disturbances in the gut microbiota, such as an imbalance in the beneficial/pathogenic effects and a decrease in diversity, can result in the passage of undesired chemicals and cells to the systemic circulation. Recently, the potential effect of probiotics on restoring/preserving the microbiota was also evaluated regarding important metabolite and vitamin production, pathogen exclusion, immune system maturation, and intestinal mucosal barrier integrity. Therefore, the focus of the present review is to discuss the available data and conclude what has been accomplished over the past two decades. This perspective fosters program development of the next steps that are necessary to obtain confirmation through clinical trials on the magnitude of the effects of kefir in large samples.