Ability of the Normal Human Small Intestine to Absorb Fructose: Evaluation by Breath Testing

Abstract

Background-Fructose consumption is rising and its malabsorption causes common gastrointestinal symptoms. Because its absorption capacity is poorly understood, there is no standard method of assessing fructose absorption. We performed a dose response study of fructose absorption in healthy subjects in order to develop a breath test to distinguish normal from abnormal fructose absorption capacity.

Simultaneous Ingestion of Fructose and Fat Exacerbates Postprandial Exogenous Lipidemia in Young Healthy Japanese Women

“…In this study, the subjects ingested a moderate amount of fructose (0.5 g/kg body weight). Although other studies have employed 0.75-1.5 g/kg of fructose 7,17) , these high amounts of fructose often induce malabsorption that causes gastrointestinal symptoms, for example bloating, abdominal pain and diarrhea [18][19][20] . HFCS-sweetened beverages contain approximately 20-30 g/500 mL of fructose 21) .…”

Prevalence of Fructose Malabsorption in Patients With Irritable Bowel Syndrome After Excluding Small Intestinal Bacterial Overgrowth

“…1 The unabsorbed fructose may play a role in osmotic load and is therefore rapidly propelled into the colon, where its contact with anaerobic microbiomes causes fermentation and the production of gaseous feeling, abdominal bloating, and even diarrhea. 8,9 Because these symptoms are very similar to functional gastrointestinal disorders, including irritable bowel syndrome (IBS), the relationship between FM and IBS has been studied. 7 However, the results have been equivocal, with the prevalence of FM in patients with IBS varying according to study designs.…”

“…Hydrogen breath testing (HBT), which detects end-expiratory alveolar hydrogen or methane gases, has been used to diagnose FM. 1,8 A high percentage of patients with IBS have small intestinal bacterial overgrowth (SIBO), which is also diagnosed by HBT. 10 However, HBT results from individuals with SIBO depend on hydrogen or methane gas concentrations.…”

“…11 Since patients with SIBO have abnormal bacterial overgrowths in their small intestines, fructose ingested during HBT for the diagnosis of FM can be fermented by these small intestinal bacteria, leading to the misdiagnosis of FM. 8 Therefore, it is necessary to exclude SIBO to assess the prevalence of FM in patients with IBS. Moreover, no studies have compared the prevalence of FM and dietary habits between patients with IBS and asymptomatic control individuals after the exclusion of SIBO.…”

“…Moreover, no studies have compared the prevalence of FM and dietary habits between patients with IBS and asymptomatic control individuals after the exclusion of SIBO. In addition, the ideal amount of fructose that should be used in the HBT for diagnosis of FM is unclear, 8,11 and the optimal fructose cut-off dose for Asian populations has not been fully evaluated. Therefore, we evaluated the prevalence of FM in patients with IBS and asymptomatic control individuals after excluding SIBO using glucose HBT.…”