title: Fructose malabsorption: how much fructose can a healthy subject tolerate?
abstract: OBJECTIVE
  In a prospective study, we evaluated fructose absorption capacity in 17 healthy female volunteers aged 16-27 years.
  
  
  METHODS
  All volunteers underwent analysis of their daily food intake diary and standardized breath tests. The volunteers were challenged consecutively with oral intake of 50, 25 and 15 g of fructose.
  
  
  RESULTS
  The average daily ingestion of fructose (19.54 ± 14.95 g) was not different between volunteers with positive and negative breath tests. On day 1, 53% of subjects exhibited a significant (≥20 ppm) increase in breath hydrogen and gastrointestinal symptoms upon challenge with 50 g of fructose. Moreover, 37.5% of the volunteers with a negative breath test became positive upon a second challenge with 50 g of fructose but remained asymptomatic. On day 2, 1 of the 9 volunteers (12.5%) with a positive breath test on day 1 exhibited an asymptomatic positive breath test upon exposure to 25 and 15 g of fructose on day 3. The 8 volunteers with a negative test (25 g of fructose) remained negative after a second exposure to 25 g of fructose.
  
  
  CONCLUSIONS
  The results of this study indicate that hydrogen breath tests with fructose challenge of 50 g of fructose are inappropriate to characterize clinically significant fructose malabsorption.
authors.affiliation: Department of Gastroenterology, Hepatology, Infectiology, Neurogastroenterology, Hematology and Oncology, HELIOS Clinic Krefeld, Krefeld, Germany. thomas.frieling@helios-kliniken.de
authors.forename: T
authors.initials: T
authors.lastname: Frieling
authors.forename: R
authors.initials: R
authors.lastname: Kuhlbusch-Zicklam
authors.forename: S
authors.initials: S
authors.lastname: Kalde
authors.forename: J
authors.initials: J
authors.lastname: Heise
authors.forename: A
authors.initials: A
authors.lastname: Hülsdonk
authors.forename: C
authors.initials: C
authors.lastname: Kreysel
mesh_terms: D015746:Abdominal Pain / Q000209:etiology; D000293:Adolescent; D000328:Adult; D001944:Breath Tests; D003967:Diarrhea / Q000209:etiology; D015930:Diet Records; D005260:Female; D005414:Flatulence / Q000209:etiology; D005632:Fructose / Q000008:administration & dosage / Q000493:pharmacokinetics*; D006801:Humans; D006859:Hydrogen / Q000032:analysis; D007408:Intestinal Absorption; D008286:Malabsorption Syndromes / Q000150:complications / Q000175:diagnosis* / Q000378:metabolism*; D011446:Prospective Studies; D055815:Young Adult
chemical_list: D005632:Fructose; D006859:Hydrogen