The word to the nutritionist, Fabio Bussacchini

My name is Fabio Bussacchini and I am a Nutritionist. I have been working in nutrition for over twenty years and my passion has always been in the study of the perfection of our organism and the balance of the triad: mind, body, spirit.

When I began studying the microbiota (never stopped) I immediately understood that we are guests of our bacteria and that, therefore, the latter must be respected, nourished and cared for.

Unfortunately, modern nutrition has forgotten good nutritional practices in favor of an industry increasingly focused on business rather than consumer health.

Foods are increasingly less rich in nutrients, vitamins and minerals as well as probiotic bacteria.

From this, it is necessary to turn our diet towards products that are truly beneficial for us and for our bacteria. These products can all be traced back to the family of fermented foods.

In 2021, the International Scientific Association for Probiotics and Prebiotics (ISAPP) published a consensus statement on the definition of fermented foods: “ Fermented foods are foods obtained through the desired microbial growth and enzymatic conversions of food components .”

Historically, man has always introduced fermented foods through his diet, consuming foods rich in ferments or more recently fermented.

The industrialization of foods and especially the intense treatments to which industrial foods are subjected have, in fact, led to a “sterilization” of foods with the consequent loss of live ferments.

This has led to an impoverishment of the intestinal bacterial flora; in particular, 1500 bacterial species have been identified that populate our intestine (and 6000 families of viruses!). The modern varied diet lowers this number to about 500 while a monotonous diet (the one followed by the majority of people on the planet) leads to having only 150-200 species.

This, unfortunately, translates into a drastic decrease in the variability of our microbiota and, consequently, to a whole series of problems due to a low presence of probiotic strains within our intestine (especially Lactobacillus spp. and Bifidobacterium spp .).

Given this, it becomes really important to enrich our diet with fermented foods.

The peculiarity of these foods, in addition to being fermented, also lies in the fact that they are not subjected to heat treatments so as to guarantee the vitality of the ferments contained in them. Most fermented foods are subjected to pasteurization which nullifies their beneficial effects. Heat treatments are carried out to increase the durability of the product and to correct any fermentation errors. The product, however, does not possess any beneficial bacterial properties!

Fermented foods that contain high levels of organic acids from fermentation (>100 mM) (e.g. lactic, acetic, malic acid, etc.), combined with low water activity and low pH are considered microbiologically safe, since these variables favor the proliferation of probiotic species to the detriment of pathogenic ones.

Food fermentations can also improve the healthiness of foods and their nutritional quality by removing toxic or anti-nutritional compounds from raw materials. This occurs, for example, in the fermentation of cereals, legumes and tubers. During fermentations, some bacterial species cancel the action of phytates (a family of compounds associated with cereals that bind divalent cations - calcium, magnesium, etc. - and reduce their natural absorption in the gastrointestinal tract). This results in increased bioavailability of calcium, magnesium, iron and zinc. It is also hypothesized that fermentation of sourdough reduces the concentration of other immune-reactive proteins, including the amylase-trypsin inhibitor in wheat, and may therefore be better tolerated than conventional breads by subjects with wheat intolerance.

Microbial activity produced by food fermentations leads to the enrichment and/or removal of compounds that affect the nutritional composition of the final food product. Microorganisms reduce the concentrations of high-calorie monosaccharides and disaccharides (glucose, sucrose, and fructose) present in milk, meat, and plants through catabolic pathways. Reductions in certain sugars may also reduce the glycemic index and improve food tolerability (e.g., lactose in dairy products, fructans in wheat, or raffinose, stachyose, and verbascose in soy and legumes).

Fermentation may involve the hydrolysis of polysaccharides, proteins or fats, thus increasing their digestion. Other enzymatic reactions also occur, including deactivation and/or degradation reactions (e.g. inactivation of seed trypsin inhibitor).

For foods containing polyphenols, the conversion of phenolic compounds by lactobacilli increases the bioavailability of flavonoids, tannins and other bioactive compounds. The biosynthesis of vitamins, amino acid derivatives, organic acids and cofactors can also occur during fermentation, with effects at the local gastrointestinal or systemic level (it is now known that most bacteria are able to produce vitamins).

Numerous human studies have shown that microorganisms in fermented foods can survive gastric transit and reach the colon, exerting their beneficial action there. Since approximately 70% of the human immune system is located in the gastrointestinal tract, foods and beverages are the main channel of contact between external antigens and the human body.

The gastrointestinal tract is vulnerable to the initial pattern of microbial colonization during the first months of life, activating a critical window for the effects of microbial stimuli on the system. In a cross-sectional study, intake of fermented foods (fermented vegetables) during early childhood was associated with a reduced risk of childhood atopy.

In another epidemiological study, the consumption of fermented foods combined with basic common hygiene rules also reduced the risk of childhood allergies.

The authors of the first study also reported that an anthroposophic lifestyle (low use of antibiotics and vaccinations and high intake of fermented vegetables) was associated with differences in the structure of the infant microbiome, including a greater abundance and diversity of bacterial strains and a higher concentration of acetate compared to children with a “traditional” lifestyle.

Fermented food intake is also one of the synergistic factors associated with agricultural education, a lifestyle factor that has been consistently associated with a reduced risk of allergies and asthma.

These associations may indicate that the lack of fermented foods in modern, industrialized societies constitutes a substantial loss of exposure to harmless microorganisms important for the development and maintenance of the immune system.

The scientific article is reported as a bibliography of this article.