Gastrointestinal Diseases Research Unit, Queen’s University, Kingston, ON K7L 2V7, Canada
Department of Dietetics, Nutrition and Sport, La Trobe University, Melbourne 3086, Australia
Allergy Unit, Department of Dermatology, University Hospital Zurich, 8091 Zurich Switzerland and Christine-Kühne Center for Allergy Research and Education CK-CARE, 7265 Davos, Switzerland
Department of Gastroenterology, University Hospital Zurich, 8091 Zurich, Switzerland
Author to whom correspondence should be addressed.
Nutrients 2019, 11(7), 1684; https://doi.org/10.3390/nu11071684
Received: 10 June 2019 / Revised: 18 July 2019 / Accepted: 18 July 2019 / Published: 22 July 2019
(This article belongs to the Special Issue Food and Diet for Gut Function and Dysfunction)
Food intolerances are estimated to affect up to 20% of the population but complete understanding of diagnosis and management is complicated, given presentation and non-immunological mechanisms associated vary greatly. This review aims to provide a scientific update on common food intolerances resulting in gastrointestinal and/or extra-intestinal symptoms. FODMAP sensitivity has strong evidence supporting its mechanisms of increased osmotic activity and fermentation with the resulting distention leading to symptoms in those with visceral hypersensitivity. For many of the other food intolerances reviewed including non-coeliac gluten/wheat sensitivity, food additives and bioactive food chemicals, the findings show that there is a shortage of reproducible well-designed double-blind, placebo-controlled studies, making understanding of the mechanisms, diagnosis and management difficult. Enzyme deficiencies have been proposed to result in other food sensitivities including low amine oxidase activity resulting in histamine intolerance and sucrase-isomaltase deficiency resulting in reduced tolerance to sugars and starch. Lack of reliable diagnostic biomarkers for all food intolerances result in an inability to target specific foods in the individual. As such, a trial-and-error approach is used, whereby suspected food constituents are reduced for a short-period and then re-challenged to assess response. Future studies should aim to identify biomarkers to predict response to dietary therapies.