Are adverse food reactions linked to irritable bowel syndrome?
OBJECTIVE
We undertook to determine whether adverse food reactions play a role in irritable bowel syndrome (IBS).


METHODS
A systematic review of the literature using Medline (1980-1996), targeting IBS and adverse food reactions, was performed. All clinical trials whereby dietary exclusion was followed by food challenge were selected. Each study was reviewed using a structured format to examine methodological issues and study outcomes.


RESULTS
Of the seven studies included, the positive response to an elimination diet ranged from 15% to 71%; double-blind placebo-controlled challenges identified problem foods in 6% to 58% of cases. Milk, wheat, and eggs were most frequently identified to cause symptom exacerbation; of the foods identified the most common trait was a high salicylate content. Foods high in amines were also identified. Studies of diarrhea-predominant IBS identified a higher percentage of adverse food reactions. However, all studies had major limitations in their trial designs, including inadequate patient selection, appropriateness of--and duration of--exclusion diets, and methods of food challenge.


CONCLUSIONS
Whether adverse reactions to foods are a key factor in exacerbating IBS symptoms or whether dietary manipulation is a valid treatment option is unclear. Carefully designed controlled clinical trials are now needed to specifically test the potential role of adverse food reactions in diarrhea-predominant IBS.
Niec
A M
AM
Department of Medicine, University of Sydney, Nepean Hospital, Penrith, NSW, Australia.
Frankum
B
B
Talley
N J
NJ
D002986:Clinical Trials as Topic; D003109:Colonic Diseases, Functional / Q000209:etiology*; D004311:Double-Blind Method; D005502:Food / Q000009:adverse effects*; D005512:Food Hypersensitivity / Q000150:complications*; D006801:Humans; D012107:Research Design