The Impact of Immunomodulatory Components Used in Clinical Nutrition-A Narrative Review

Malnutrition is a clinical condition that leads to unfavourable changes in health. It affects 35-55% of hospitalized patients, and in the case of cancer, this prevalence rises to 40-90% of patients. Screening nutritional status is essential for preventing undernutrition, which is crucial as its treatment. Undernutrition in patients after severe injuries significantly increases catabolic changes. Cytokines and hormones, such as epinephrine, glucagon, and cortisol, are released, which can increase energy expenditure by 50%. Properly conducted nutritional treatment aims to maintain or improve the nutritional status of patients whose nutrition with a natural diet is insufficient, moreover, in some cases, treatment of the underlying disease.

This study is a narrative review focused on immunonutrition. The search for source articles, mainly from the last 10 years, was conducted in the PubMed and Google Schoolar databases, as well as in printed books. The key words used were "malnutrition", "inflammation", "clinical nutrition", "immunomodulatory components", "nutritional status assessment", "enteral nutrition", "parenteral nutrition", and their combinations.

Providing substances such as omega-3 fatty acids, glutamine, arginine, nucleotides, antioxidants, and prebiotic fiber has a beneficial impact on immunological and anti-inflammatory pathways. The above-mentioned ingredients may inhibit the secretion of pro-inflammatory cytokines, activate anti-inflammatory cytokines, stimulate immune cells, and have a beneficial effect in allergic diseases, respiratory infections, or wound healing.

Immunonutrition can be administrated via oral, enteral, and parenteral routes. It is crucial to highlight the importance of proper nutritional status in patients. The relationship between inflammation and malnutrition creates a vicious cycle, where one negatively affects the other due to increased metabolic demand, loss of appetite, weakened immune system, and gut dysbiosis.