Metabolic effects of a diet with inulin-enriched pasta in healthy young volunteers

Different lines of evidence suggest that higher intake of fiber may somehow protect against metabolic syndrome. The prebiotic inulin has widely been studied in relation to its putative beneficial effects on lipid and glucose metabolism. Therefore, adding inulin to diet may be a suitable strategy to prevent metabolic syndrome. Aim of the present study was to evaluate the effects of the daily consumption of inulin-enriched pasta on lipid and glucose metabolism as well as on gastrointestinal motility in young healthy subjects. Methods. Twenty-two healthy young male volunteers entered a randomized double blind cross-over study consisting of a 2-weeks a run-in period, two 5-weeks study periods (11% inulin-enriched or control pasta), and an 8-weeks wash-out period in between. Serum lipid and glucose concentrations were evaluated by routine biochemical analyses. Gastric emptying time and electrical activity were non-invasively evaluated by ultrasound and electrogastrography. Data were analyzed by Friedman Repeated Measures ANOVA test. Results. Significant differences among baseline and the treatment group were found for HDL-cholesterol (p=0.004), total cholesterol/HDL-cholesterol ratio (p=0.006), triglycerides (p=0.04), fasting glucose level (p=0.044), fructosamine (p=0.0478), HbA1c (p=0.04), and homeostatic model assessment (HOMA-IR) (p=0.045). The gastric emptying, expressed as final emptying time, was found significantly delayed in the group that assumed inulin-enriched pasta (p=0.008). Conclusions. Inulin-enriched pasta improved lipidic and glicidic metabolism as well as the insulin resistance in healthy young subjects. In addition, it delayed the gastric emptying time which may represent the physiological counterpart of its metabolic effects.