IS THERE A RELATIONSHIP BETWEEN INTESTINAL FRUCTOSE MALABSORPTION, GASTROINTESTINAL SYMPTOMS AFTER FRUCTOSE OVERLOAD,...

Over the past several decades, dietary fructose intake has increased significantly, along with the prevalence of obesity. Fructose malabsorption is associated with gastrointestinal symptoms and may lead to fructose intolerance. Evidence suggests a probable association between intestinal fructose malabsorption and increased body adiposity.

To analyze the prevalence of intestinal fructose malabsorption and intolerance in asymptomatic adolescents and to investigate their relationship with fructose intake, body adiposity, systemic metabolic indicators, and intestinal permeability.

This cross-sectional observational study included 37 adolescents without gastrointestinal symptoms. Fructose malabsorption was investigated using the hydrogen breath test along with the lactulose breath test. Food intake was evaluated using a habitual food survey. Nutritional status was assessed by measuring weight, height, skin folds, abdominal circumference, and via Bioelectrical Impedance Analysis (BIA). Systemic metabolic indicators and serum zonulin levels were also evaluated to determine intestinal permeability.

Of the 37 adolescents tested 16 (43.2%) exhibited fructose malabsorption. Gastrointestinal symptoms compatible with fructose intolerance were reported by 8 (50.0%) of the 16 adolescents with fructose malabsorption, and by 5 (23.8%) of the 21 adolescents without fructose malabsorption (P=0.095). Fructose intake among adolescents with and without fructose malabsorption was 7.5 and 7.9 g/day, respectively (P=0.807). Body adiposity was comparable across groups in both females (34.2% and 33.2%; P=0.738) and males (21.0% and 22.2%; P=0.731). Metabolic indicators and zonulin levels were similar, except for urea, which was significantly higher in the malabsorption group (31.7±6.3 mg/dL) compared to those without fructose malabsorption (24.5±÷7.8 md/dL; P=0.012).

Intestinal fructose malabsorption is common in asymptomatic adolescents and is not associated with adiposity, biochemical changes, or increased intestinal permeability. However, it correlates with elevated fermentation in the lactulose breath test. Fructose intolerance is linked to presence gastrointestinal symptoms following lactulose ingestion.