Gut microbiota, the keys to a long life

 Gut microbiota, the keys to a long life at the center of the body

It is now known that the gut microbiota is important for skin, morale, and immunity, and scientists claim that it is also one of the keys to a long life. Here are some explanations.

After decades of wondering what the secret of centenarians was, Japanese scientists may have discovered one of the keys to their longevity. According to a study from Keiō University in Tokyo, published in Nature last summer, it may lie in the gut. Researchers discovered that the gut microbiota of people over 100 years old has a specific population of bacteria that can produce secondary bile acids that protect against certain highly resistant pathogens. Thus, these beneficial bacteria help maintain a good balance in the intestinal flora and promote a symbiotic relationship between this flora and the host organism.

A very personal event

The new study supports what some researchers, such as Professor Paul O'Toole, a microbiologist at the University of Cork and a member of the European Eldermet project (which studies the microbiota of older people), have assumed for years: that what we have in our gut can determine how quickly we age. In older people, the microbiota changes, explains Joël Doré, head of research at INRAE's Institut Michalis in Jouy-en-Josas. With age, the microbiota loses its richness and diversity, mainly due to a physiological decrease in the production of protective mucins and changes in digestion, but often also due to a monotonous diet. This loss of richness is accompanied by a reduction in the effectiveness of natural defense mechanisms and a decrease in resistance to pathogens.

The superpowers of the billions of bacteria, viruses, and other fungi that colonize our digestive system are not limited to digestion: by blocking the passage of inflammatory and pathogenic substances, constantly talking to the brain, producing small molecules called metabolites, and then releasing them into the bloodstream, they also intervene in the regulation of immune, metabolic and neurological functions.

All major modern diseases probably have an important macrobiotic component," says the researcher. Dysbiosis (an imbalance of the intestinal flora with a decrease in bacterial richness in favor of an abundance of pathogenic bacteria) is harmful because it leads to a disruption of the relationship between the individual and his or her various microbiota. Therefore, over time, these changes contribute to the deterioration of the immune system, to the development of vulnerabilities, and can lead to certain risks or pathologies: chronic inflammation, cognitive impairment, type 2 diabetes, cardiovascular diseases, and cancer.

Prebiotics based on anti-aging strains

Can we really delay aging by acting on the contents of our gut? "It's more subtle than that, says Jean-Paul Motta, a researcher at the Digestive Health Research Institute (Inserm) in Toulouse. Each microbiota develops in its own way and adapts over time. Therefore, there is no universal composition of the microbiota for long and healthy life. It is also necessary to take into account the relationship between the individual and his bacteria, as well as their behavior in communities and their geographical location in the gut. All these ideas open up therapeutic possibilities, but we need to understand them better to adapt them to each individual."

New companies are already working on prebiotic therapies based on anti-aging strains. Researchers are also experimenting with stool transplants, which could eventually cure certain diseases or compensate for certain defects, just like organ transplants. In the meantime, the best way to keep your plate clean "is to eat a varied and colorful diet, mainly plant-based, with a low consumption of alcohol, especially processed products and red meat, and to increase fiber intake, both in quantity and variety," says Joël Doré. Probiotic treatments? Try it for a month. If you don't notice any change, stop or change the variety.

The protective properties of fasting

Fasting, whether intermittent or consecutive, is also a promising way to fight the ravages of time. "Clinical and laboratory studies show that it is one of the most effective ways to activate the processes of cell protection, cell repair, and cell rejuvenation," says Professor Valter Longo, the gerontologist who developed the diet. In addition to the detoxifying effect on the intestinal microbiota (more friendly and less harmful bacteria), it would be possible to "effectively limit energy intake without side effects, with significant benefits in terms of aging and disease risk factors."

This means not eating (but also not drinking) for 14-16 hours and skipping breakfast or dinner, depending on your habits, lifestyle, and appetite. In order not to skip anything, it is advisable to follow the daily dietary recommendations (5 fruits and vegetables, 2 servings of vegetable or animal protein, 3 dairy products, etc.), but two meals, not three.