Nutrients 2013, 5, 162-207; doi:10.3390/nu5010162 OPEN ACCESS nutrients ISSN 2072-6643 www.mdpi.com/journal/nutrients Review Nutrition of the Critically Ill—A 21st-Century Perspective Stig Bengmark Division of Surgery & Interventional Science, University College London, 4th floor, 74 Huntley Street, London, WC1E 6AU, UK; E-Mail:
[email protected]; Tel.: +44-20-7511-6842 Received: 16 November 2012; in revised form: 17 December 2012 / Accepted: 24 December 2012 / Published: 14 January 2013 Abstract: Health care-induced diseases constitute a fast-increasing problem. Just one type of these health care-associated infections (HCAI) constitutes the fourth leading cause of death in Western countries. About 25 million individuals worldwide are estimated each year to undergo major surgery, of which approximately 3 million will never return home from the hospital. Furthermore, the quality of life is reported to be significantly impaired for the rest of the lives of those who, during their hospital stay, suffered life-threatening infections/sepsis. Severe infections are strongly associated with a high degree of systemic inflammation in the body, and intimately associated with significantly reduced and malfunctioning GI microbiota, a condition called dysbiosis. Deranged composition and function of the gastrointestinal microbiota, occurring from the mouth to the anus, has been found to cause impaired ability to maintain intact mucosal membrane functions and prevent leakage of toxins—bacterial endotoxins, as well as whole bacteria or debris of bacteria, the DNA of which are commonly found in most cells of the body, often in adipocytes of obese individuals or in arteriosclerotic plaques. Foods rich in proteotoxins such as gluten, casein and zein, and proteins, have been observed to have endotoxin-like effects that can contribute to dysbiosis.