| Abstract: |
This chapter about food allergies is from a comprehensive textbook that compiles available data, clinical experience, and research on the role of nutrition in the management of patients with disorders that affect the gastrointestinal (GI) tract. The authors describe the problem when food proteins, although indispensable for life, become harmful when recognized by the immune system as foreign antigens. When this happens, food proteins trigger an abnormal immune response and subsequently an inflammatory reaction, which can vary in extent and duration. Allergic reactions to food frequently occur in early childhood and disappear spontaneously within the first 4 to 6 years of life. The authors define adverse reactions to food (ARF), noting that they are caused by a variety of mechanisms, with only about a third of the reactions in children and 10 percent of those in adults being due to an abnormal immunological reaction to food. The chapter reviews the cellular and molecular mechanisms of food allergy; the biochemistry of food allergens; the clinical classification of food allergy, notably non-GI manifestations, GI manifestations, latex-food allergy syndrome, food protein enteropathy and food protein enterocolitis or proctitis, and eosinophilic esophagitis and gastroesophageal reflux disease (GERD); nonimmune ARF, including pseudoallergic and pharmacologic reactions, lactose intolerance, psychological intolerance, and physiological food intolerance; and diagnosis and treatment strategies. The authors conclude with a brief discussion of a new understanding of the role of innate defense systems and the gut microflora, which have opened exciting new therapeutic options such as the use of probiotic bacteria for treatment and prevention of food allergy. 3 tables. 95 references. |