title: Sugar malabsorption in functional bowel disease: clinical implications.
abstract: OBJECTIVE
  To investigate the relationship of sugar malabsorption to the development of clinical symptoms in functional bowel disease.
  
  
  METHODS
  Twenty-five consecutive outpatients [five men, 20 women; mean age 38.7 +/- 2.6 (SEM) yr] with functional bowel disease and symptoms suggestive of carbohydrate malabsorption were studied. Twelve healthy subjects [six men, six women; mean age 35.7 +/- 3.7 (SEM) yr] acted as the control group. Sugar malabsorption was assessed by breath-hydrogen test after an oral load of various solutions containing lactose (50 g), fructose (25 g), sorbitol (5 g), fructose plus sorbitol (25 + 5 g), and sucrose (50 g). The severity of symptoms developing after sugar challenge was studied. In addition, the effect on clinical symptoms of a diet free of the offending sugars, compared to a low-fat diet, was assessed.
  
  
  RESULTS
  Frequency of sugar malabsorption was high in both patients and controls, with malabsorption of at least one sugar in more than 90% of the subjects. Median symptom scores after both lactose [median 6; interquartile (IQ) range 3-7] and fructose plus sorbitol (median 2; IQ range 0-4) malabsorption were significantly higher than after sucrose load (median 1; IQ range 0-1.5) in functional bowel disease patients (p = 0.001 and p = 0.007, respectively). However, there were no differences in healthy controls. In addition, symptoms score after both lactose and fructose plus sorbitol malabsorption was significantly higher in patients than in control subjects (p = 0.02 and p = 0.008, respectively). On the other hand, H2 production capacity, as measured following lactulose load, was significantly higher in patients than in controls. The clinical symptoms improved in 40% of the evaluated patients after restriction of the offending sugars.
  
  
  CONCLUSIONS
  These results suggest that sugar malabsorption may be implicated in the development of abdominal distress in at least a subset of patients with functional bowel disease.
authors.affiliation: Department of Gastroenterology, Hospital Universitari Germans Trias i Pujol, Badalona, Spain.
authors.forename: F
authors.initials: F
authors.lastname: Fernández-Bañares
authors.forename: M
authors.initials: M
authors.lastname: Esteve-Pardo
authors.forename: R
authors.initials: R
authors.lastname: de Leon
authors.forename: P
authors.initials: P
authors.lastname: Humbert
authors.forename: E
authors.initials: E
authors.lastname: Cabré
authors.forename: J M
authors.initials: JM
authors.lastname: Llovet
authors.forename: M A
authors.initials: MA
authors.lastname: Gassull
mesh_terms: D000328:Adult; D001944:Breath Tests; D003109:Colonic Diseases, Functional / Q000175:diagnosis / Q000209:etiology / Q000378:metabolism* / Q000523:psychology; D003937:Diagnosis, Differential; D004040:Dietary Carbohydrates / Q000378:metabolism*; D005260:Female; D005632:Fructose / Q000378:metabolism; D006801:Humans; D007408:Intestinal Absorption; D007785:Lactose / Q000378:metabolism; D007792:Lactulose / Q000378:metabolism; D008286:Malabsorption Syndromes / Q000175:diagnosis; D008297:Male; D008875:Middle Aged; D013012:Sorbitol / Q000378:metabolism; D013395:Sucrose / Q000378:metabolism
chemical_list: D004040:Dietary Carbohydrates; D005632:Fructose; D007792:Lactulose; D013012:Sorbitol; D013395:Sucrose; D007785:Lactose