Probiotics And Prebiotics, What Are They?
Probiotics and prebiotics are recently widely used words especially in the cosmetics sector, let’s see what they are.
The term ‘probiotic’ derives from the Greek “pro-bios” which means “for life”, “in favor of life”. According to the WHO definition, they are “living organisms which, if administered in adequate quantities, bring a benefit to the host health”. They can be integrated from the outside (through food and supplements) and live within our skin microbiota.
A microorganism can be considered probiotic if it meets the following requirements:
• it must be safe for use in humans: probiotic microorganisms must not carry acquired and/or transmissible antibiotic resistance;
• they must be able to confer a demonstrated physiological benefit.
Prebiotics, on the other hand, are the nourishment for our good bacteria. They are organic substances (carbohydrates and olysaccharides) that stimulate the good bacteria growth that make up the skin microbiota. They are able to support the bacteria energy metabolism that make up our microflora, optimize the environment that hosts it, and improve the physiological balance in general.
What Is The Cutaneous Microbiota?

The skin, the largest organ in our body as well as the first barrier against external aggressions, is physiologically colonized by countless species of microorganisms, especially bacteria, but also fungi, viruses and archaea which together make up the skin microbiota.
The composition and expression variability of these microorganisms is extremely high, recording substantial differences not only inter-individual but also intra-individual.
The face microbiota can differentiate from neck microbiota, as well as change in a time-dependent manner. It also varies according to the sebum amount, as the microorganisms that populate our body wettest areas such as armpits, groin, feet soles, that are different from those that populate the areas richest in sebaceous glands such as the forehead, nose and scalp. Due of these variables, research has many difficulties in defining the ideal microbiota profile, able to keep our skin healthy.
The only aspect in which there is scientific evidence is that a skin microbiota imbalance would seem to be involved in the skin disorder onset or, in some cases, in epithelial pathologies.
There are several factors that influence the microbiota composition on body different parts: humidity, temperature, pH, energy resources available for the metabolism of bacteria.
The microbiota therefore represents the whole microorganisms population that live in symbiosis with us, on our skin, but also in our intestines.
What Are Probiotic Cosmetics And What Are They For
In order to achieve and maintain skin balance, new cosmetic products functionality are studied in the cosmetic sector, focusing on skin commensal microorganisms through the probiotics application, thus bringing the “friendly” microorganisms directly to the skin, or enriching the products cosmetic with prebiotics, therefore of substances that favor the microorganisms species development that protect the physiological skin functions to the pathogens detriment.
As for the probiotics use, the difficulty in defining the ideal skin microbiota profile is also reflected in the cosmetic products development designed with the aim of keeping it in good condition: the probiotics application on the skin is of great interest for the world of research, but unlike probiotics taken orally, we are trying to define which is the most valid strategy, as there are several formulation problems.
Working with probiotics in cosmetics is problematic because any microbial growth in cosmetics affects the product safety and contravenes the regulatory provisions, resulting incompatible with the regulatory requirements that must guarantee its stability: the water and substances presence useful for microorganisms growth and maintenance or storage at room temperature are factors that favor bacterial proliferation leading to alter the cosmetic structure.
However, this is a field of considerable interest, in which major players in world cosmetics have also registered some patents concerning probiotic derivatives, such as lysates which, despite being inactive, can bring the live microorganism benefits to the skin, acting as probiotics, transporting on the epidermis those bacteriostatic substances, the so-called bacteriocins, useful in controlling microbial growth. The postbiotics use, that is derived from the metabolism of bacteria, is widespread.
What Are Prebiotic Cosmetics And What Are They For




The situation is different for prebiotics in the cosmetic sector, as they are organic substances and not microorganisms, such as fibers and sugars, such as: inulin, glycosaminoglycans, beta-glucans, lactulose, oligofructosaccharides, produced by biotechnology or extracted from sources vegetables.
Their use, therefore, is well manageable in product development, remaining in a completely cosmetic environment and without problematic regulatory overruns.
Differences Between Probiotic And Prebiotic Cosmetics
Probiotics, the so-called “good bacteria“, strengthen the skin barrier, keeping the skin hydrated and regulating the production of sebum. The most used are lactobacilli and bifidobacilli.
Applying a topical probiotic cream or solution to the skin can help manage the balance of the healthy bacteria that make up the skin microbiome. The probiotics within these creams can help reduce the skin pH by slightly acidifying its surface to help reduce the growth of external bacteria and promote the thriving of healthy bacteria on the skin.
Prebiotics are the probiotics nourishment which constitute the fertile ground through which probiotics can live, rebalance the composition of the microflora and also optimize the environment.
They are included in the creams and emulsions formulation, shampoos, lotions for the scalp.
The prebiotic creams application on the skin can be extremely beneficial as it helps to preserve the healthy bacteria existing on the skin and promotes the probiotic microorganisms growth and survival already present in the skin microbiome.
How The Skincare Routine Changes With Prebiotic And Probiotic Cosmetics
By “feeding” our microbiota, the skin will benefit: the skin balance is the precursor that allows us to maintain healthy skin. When this balance is compromised, the skin is dry with an imbalance of the sebum, the presence of psoriasis or other inflammatory diseases.
Consequently, adopting a correct skincare routine with cosmetic products that contain probiotics and prebiotics can be of help in the case of various skin problems.