In the light of recent discoveries on how much human health can depend on elements that until a few years ago were considered to belong only to organ pathologies (intestine or heart or brain separately), today it can be stated that the interaction of each cell stem, be it of the central nervous system, of the heart, of the lung or that regulates the immune system, must be understood as a complex and interacting entity, where in a surprising way it has been seen that one of the conductors are the germs that inhabit in our intestines, much higher in number than the cells that make up our body.
Important roles
The population of microorganisms that colonize our intestines is called microbiota; it influences the regulation of digestion, metabolism, synthesizing vitamins and releasing molecules that contribute to intestinal well-being, but it also has other important roles, such as cooperating with the immune system, assuming the ability to guide the organism towards a protective system from pathogenic microbes and toxic substances; it has also been identified that the metabolites produced by intestinal bacteria intervene on the central nervous system, including the regulation of mood, stress and the sense of satiety, earning the nickname of “second brain”, also acting on the psychological state, contributing to coordinate the hypothalamic-pituitary-adrenal axis.
Internal balance
As evidence accumulates on the importance of these germs for human health, the desire to stimulate their active and beneficial part with supplements grows exponentially. First came the probiotics, live bacteria useful for the intestine, then the prebiotics, or foods particularly dear to the development and health of the microbiota; recently, postbiotics have been added to this group, dead bacteria that would be more effective in regulating and maintaining a state of “eubiosis” and therefore of balance within our intestines: the new theater of origin of many disorders.
«Given that the first, pre and probiotics have not convinced over the years due to the variable and not always uniform clinical responses – says Professor Colin Hill, microbiologist at the University of Cork – postbiotics are instead arousing ever-increasing interest for the clinical benefits on the skin , on the muscles and above all on the treatment of many disorders of the intestinal sphere ».
As Harriet Schelekens, a scientist at the same Irish University explains, «the one hundred trillion bacteria, viruses and fungi that inhabit our intestines collaborate in a surprising way in regulating immunity, energy level, mood, up to regulating hormonal structures including insulin , leptin but also estrogen and progesterone».
However, this microbial heritage is sensitive and easily suffers from unbalanced eating habits, such as protracted antibiotic therapies or improper and prolonged use of drugs.
Consider that a week of antibiotic therapy can alter the microbiota for a period of 6 months. Here probiotics have come to the rescue, the so-called “lactic ferments”, designed to favor a more rapid recovery of the friendly bacterial population, which has been on the pharmacy counters for decades, to the point that the value of the probiotic industry, which is constantly growing , reached 60 billion dollars in 2021.
The prebiotic cousins, good food supplements for our bacteria, although with some scientific evidence that testifies to their usefulness in regulating food intake or maintaining good bone density, have not convinced the scientific communities 100%; this is due to the great variability of answers and interactions.
Here are the postbiotics, basically dead microbes, more useful than you can imagine, rich in enzymes, vitamins, short-chain fatty acids and polysaccharides, as stated by Tim Spector of King’s College London. Short-chain fatty acids, for example, i.e. the metabolites produced by our microbiota when particular fibers are consumed, such as the inulin in leeks, bananas and asparagus, are mainly identified in butyric acid, a panacea for the immune system and to control allergies or to maintain an inflammation-free intestinal wall, as suggested by Professor Feleszko, a pediatric immunologist from Warsaw, a pioneer in describing how supplements containing butyrate as a postbiotic can even cure diseases such as ulcerative colitis or other forms of intestinal inflammation if administered like enemas.
New avenues of research have opened up, for example another promising among these is equo – lo, which is produced when soy is taken; similar in chemical structure to estrogen, some studies see it as a potential protector against breast cancer, or in regulating annoying menopausal symptoms.
Innovative research
Research in the oncological field in this regard is advancing, for example it has been highlighted that the waste products of certain intestinal lactobacilli can trigger the death of some cancer cells, adding more and more interest to the topic.
But it is not only the cancer cell that is the only target, but the aging cell. Take for example Urolithin A, a substance produced by our microbe friends when we eat walnuts, strawberries or pomegranates; it is hypothesized that it represents a powerful aid for the life of the mitochondria, the organelles that give energy to our cells and which drastically abandon us over the years.
These innovative aspects open up new scenarios on the possibility of intervening by stimulating particular effects of the microbiota, both with food and with special supplements. In fact, as Nicola Longo states «… the common denominator of the diet of places with the highest number of long-lived subjects is represented by nuts, vegetables, cereals and legumes; virtually no processed or refined foods.
Pros and cons
In some clinical studies of the Swiss company Amazentis, evidence has emerged that integration with Urolithin or other post biotics can improve the performance of elderly people (strength, resistance and mood). The only defect of these substances at the moment is the cost, still very high, which limits their diffusion. Patrice Cani, researcher at the University of Louvain in Belgium, demonstrated in a study on 32 obese diabetic subjects that supplementing the diet with strains of dead bacteria of Akkermansia muciniphila reactivates an insulin sensitivity, lowers cholesterol levels in the blood, and weight is lost, data not obtained from the control group taking placebo. Hopes and new horizons only partially dampened by Gregor Reid, professor emeritus at Western University in Ontario, who underlines “the need for high-quality clinical studies not led by the industry”, and that “it will take time to offer the population postbiotics certainly effective and low cost.
The diet
For now, in fact, concludes Reid, the safest path remains that of a diet rich in fibre, understood as vegetables of all kinds, cereals and legumes, including soy derivatives, red fruit, and avoiding processed products and above all simple sugars , the real killer of the 3rd millennium. It is also a shared opinion that to include naturally fermented products such as yogurt, kefir, miso and kombucha, a drink made from tea, in the diet, as well as any fermented food that is naturally enriched with probiotics and postbiotics.
«There is still a lot of evidence – says Harriet Shellekens – but we understood that inside our body there is a natural factory with immense potential, which if carefully studied and stimulated could in the future really represent the path to health, well-being and longevity ».
from La Gazzetta di Parma of 1/3/2023
