Fructose malabsorption has been associated with irritable bowel syndrome (IBS), but its impact
on infections of the respiratory and urogenital tracts, inflammation of the skin, as well as dyspepsia and heartburn, has not
Fructose absorptions of 62 outpatients with clinical signs of IBS were monitored by a fructose-H2- breath test.
Additionally, the urinary fructose concentration was monitored during a 2-hour test period. Patients were asked to answer
a questionnaire to evaluate their discomfort and to diagnose multiple chronic or recurrent diseases. Patients with
manifested fructose malabsorption were put on a reduced fructose diet for up to 3 years. At the end of follow-up, patients
were called in again for evaluatation of their dietary compliance and possible development of persistent complaints.
Patients with fructose malabsorption had higher urinary fructose concentrations during the fructose tolerance tests
than did normal fructose absorbers (46.7 ± 36.4 mg/dl vs. 18.7 ± 10.1 mg/dl; p<0.01). Chronic or recurrent infections of
respiratory and the urogenital tracts, inflammation of the skin, as well as dyspepsia and heartburn were more than twice as
high in fructose malabsorbers than in normal absorbers (78.1% vs. 36.7%). The risk of chronic and recurrent illnesses was
higher in the group of fructose malabsorption (p=0.002). A fructose-restricted diet significantly reduced the vulnerability
to various forms of chronic or recurrent diseases.
Chronic and recurrent infections of respiratory and urogenital tracts, inflammation of the skin, dyspepsia and
heartburn correlate with fructose malabsorption. A dietary fructose reduction was effective in reducing these illnesses.