The purpose of this literature review is to develop a thorough understanding of the research on food intolerance and its relationship to irritable bowel syndrome. Knowledge of the connection between the two conditions will assist allied healthcare professionals in working with patients to better manage their symptoms. Reduced healthcare costs may also result if patients are able to identify problematic foods and experience symptom improvement with diet changes. The review consists of an overview of food intolerance including prevalence, specific foods implicated including an in-depth review of research on bulk sweeteners, as well as methods of diagnosis. In addition, prevalence, specific foods associated with food intolerance in irritable bowel syndrome patients such as carbohydrates and lipids, nutritional consequences of food intolerance, and possible food-related methods of treatment including increased fiber intake are discussed. Finally, suggestions for future research and possible directions allied healthcare professionals can start with in assisting patients are provided.