What is the difference between microbiota and microbiome?

The microbiota is the collection of more than a trillion microorganisms, including bacteria, viruses, fungi and protozoa, that populate our bodies and communicate with each other, performing various health functions. The part of the microbiota composed of bacteria-the most abundant-is referred to as “bacteriota,” that of viruses “virota,” and that of fungi “mycota.”

Very often, however, the term microbiota is generically used to refer to gut bacteria, which have the ability to metabolize and transform the products of digestion into substances useful for health.

The term microbiome, however, is not synonymous with microbiota but indicates the genetic makeup of the microbiota, that is, the set of its genes.

Where is the microbiota found?

The microbiota is found throughout our bodies, from the skin to the mucous membranes, from the intestines to the uro-genital system.

What does the microbiota do?

Our relationship with the microbiota is based on an exchange of mutual benefits. We give the bacteria the nutrients they need, while they perform physiological, metabolic, and immunological functions important to our physical and mental well-being. Our health, therefore, is closely associated with the health status of the microbiota.

The gut microbiota, in particular, performs a number of basic functions such as producing amino acidsAmino acids are the basic substances that make up proteins. Each protein is characterized by a precise sequence of amino acid "bricks". Some are produced by the body by processing food, others, which the body cannot synthesize, must be taken directly with food., activating bile acids, metabolizing plant-derived polysaccharides (i.e., fiber), and supporting fat absorption.

What is dysbiosis?

The health status of the microbiota is defined by three factors: the total number of microorganisms, the diversity of species present, and the ratio between them. When an equilibrium condition exists, that is, when there are enough microorganisms of many different species and the “good” species have an advantage over the “bad” ones, it is called eubiosis. When, on the other hand, the balance is disturbed, so-called dysbiosis occurs, a condition observed in many diseases including inflammatory bowel, immunological, and metabolic diseases. It should be pointed out, however, that there are no absolute “good” or “bad” species: the ability of a bacterial strain to give benefits or create problems depends more on its balance in the ecosystem.

Microbiota and diet

The composition of the microbiota is unique to each individual and varies depending on several factors such as genetic makeup, type of delivery (natural or cesarean) and breastfeeding (breast or artificial), diet, and lifestyle. Speaking of the gut microbiota, certain types of bacteria are common in most people, particularly species from the taxonomic groups (phyla) of Bacteroidetes and Firmicutes(of which lactobacilli are also a part), which account for 90 percent of the gut microbiota.

The composition of the gut microbiota is partly stable throughout life and partly variable, that is, it is influenced by various factors, such as age and diet.

Because the microbiota is unique to each individual, there is no one-size-fits-all diet. The advice is to follow a diversified diet that helps increase gut microbial biodiversity and maintain species balance.

In addition, since bacteria from the variable part of the gut microbiota compete to colonize the digestive tract, particular foods or dietary supplementation may promote the proliferation of species considered “good.” ProbioticsFoods containing specific bacterial strains from the intestinal environment. are precisely foods or supplements that contain microorganisms belonging to the variable part, strains of “good” bacteria that, once ingested, manage to arrive alive and active all the way to the intestine, to settle and multiply exerting a balancing action on the entire intestinal flora.

Finally, tests on fecal samples are available to monitor the microbiota, offering valuable information for managing a personalized diet.