Impaired tolerance of indigestible carbohydrates in adults with subjective milk intolerance

Abstract

Background: Some Finns report a diminution of milk-related gastrointestinal symptoms when they travel or live abroad. Change in the overall diet may explain the diminution of symptoms. Objective: The aim was to determine whether these symptomatic subjects are actually sensitive to indigestible carbohydrates found in a typical Finnish diet. Design: Nineteen symptomatic subjects whose milk-related symptoms decreased abroad were interviewed. Symptoms and hydrogen excretion were measured after ingestion of rye bread and xylitol in six symptomatic and nine control subjects. In addition, gastrointestinal symptoms during 3 day interventions with rye and wheat bread were studied in five symptomatic subjects. Results: The symptomatic subjects experienced more symptoms than the controls after rye bread and xylitol ingestion (p=0.0003, p=0.042). Breath hydrogen excretion was similar in both groups. The symptomatic subjects experienced more symptoms during the rye bread than the wheat bread intervention (p=0.036). Conclusion: Some individuals reporting milk-related gastrointestinal symptoms may actually react to indigestible carbohydrates in the diet. Keywords: gastrointestinal symptoms; lactose malabsorption; rye bread; xylitol