Abstract

Approximately 70% of the immune system is localized in the gastrointestinal tract: its glands, mucosa, and mucosa-associated lymphoid system. The system influences health conditions because it produces large amounts of important gastrointestinal secretions as rich as breast milk in health-supporting and disease-preventing factors, and because of its rich gastrointestinal flora. The intestine normally contains 10 times more microbes than there are eukaryotic cells in the entire body. The optimal function of these microbes depends on the supply of food destined for the colonic bacteria (fermentable fibers, complex proteins, gastrointestinal secretions). The consideration of these functions influences outcome. Unfortunately, the conditions (supply of drugs-especially antibiotics, and reduced supply of food-especially fruits and vegetables) in the modern ICU are extremely poor both for optimal gastrointestinal secretion and for flora and need more attention. To improve treatment, a supply of new and effective flora (probiotics) and food for the flora (prebiotics) is needed, from which numerous health-supporting products (synbiotics) will be produced and absorbed at the level of the mucosa, mainly in the lower gastrointestinal tract.