The global scenario concerning undernutrition presents a critical challenge to public health, manifesting profound repercussions on morbidity and mortality worldwide. A notable manifestation of this issue is protein-energy undernutrition, wherein an individual's intake of essential macronutrients and proteins falls below the levels necessary for maintaining optimal health.

This condition significantly contributes to the burden of various diseases on a global scale. In regions with abundant food resources, protein-energy undernutrition has become alarmingly prevalent among specific demographics, particularly affecting the elderly and individuals grappling with conditions that impair appetite, digestion, absorption, and nutrient metabolism.

Chronic illnesses such as cancer or autoimmune disorders, infections, inflammatory conditions, metabolic disorders, and adverse drug reactions further exacerbate the prevalence of undernutrition in these populations. Indeed, Disease-Related Malnutrition (DMR) and micronutrients deficit are frequent conditions in the Inflammatory Bowel Disease (IBD) population reaching a prevalence of 23% in a recent multicentric study.

The mechanisms underlying malnutrition in IBD include reduced oral food intake due to loss of appetite, nausea, vomiting, abdominal pain, and diarrhea; malabsorption of nutrients due to leaky intestinal barrier, impaired epithelial transport, and loss of epithelial integrity; accelerated gastrointestinal transit; drugs-related micronutrients absorption and increased energy requirements due to systemic inflammation and inflammatory mediators synthesis.

The intricate interplay between undernutrition and health becomes even more pronounced with the profound alteration of intestinal structure and function. This alteration leads to impaired nutrient absorption and digestion, creating a ripple effect on associated medical conditions. The detrimental impact of inadequate nourishment extends beyond nutritional deficiencies, adversely affecting intestinal health.

The disruption of nutrient balance in the gut lumen compromises the maintenance of the intestinal barrier, leading to a cascade of effects. This includes the atrophy of intestinal villi, diminished protective mucus layer, dysbiosis, bacterial retention, and alterations in mucosal immune system functions. Collectively, these factors contribute to damage in the intestinal barrier, characterized by a reduction in tight junction proteins and increased gut permeability.

This compromised intestinal barrier, in turn, allows luminal content to leak into the submucosal space and circulation, thereby promoting both intestinal and systemic inflammation. This creates a vicious circle as inflammation further reduces appetite and increases protein consumption due to the synthesis of inflammatory mediators and to failed attempts of tissue repair. The multifaceted nature of the issue calls for holistic approaches, and the development of innovative technologies and models.

The mentioned food supplement, which is based on a novel class of natural products, namely postbiotics, i.e. essential metabolites released during the metabolic activity of bacteria capable of conferring a beneficial effect to the host in either direct or indirect way, represents a promising step towards addressing the complex challenges posed by undernutrition on a global scale. Postbiotics comprise a multitude of metabolites (around 100) released during the fermentation process, ensuring multiple functional activities from intestinal barrier protection, anti-inflammatory activities, and microbiota reshaping.