AbstractHigh sugar consumption is associated with cardiovascular diseases and diabetes. Current sugar substitutes may cause taste sensations and gastrointestinal symptoms. ENSO 16 is a combination of 16 different sugar substitutes and plant fibers and has been designed as a sugar alternative. The impact on plasma glucose metabolism as well as on gastrointestinal tolerance has not been investigated yet. 17 healthy participants were enrolled in this randomized, double-blind trial. Participants received a single oral dose of 30 g glucose or 30 g ENSO 16 and crossed over to the alternate treatment after a 7 day wash out period. The study endpoint was the effect on plasma glucose, insulin, C-peptide concentrations and gastrointestinal disorders. A questionnaire regarding gastrointestinal symptoms was used for individual subjective scoring. The mean baseline adjusted plasma glucose AUC0–180 min was significantly greater after glucose administration compared to ENSO 16 (n = 15, p = 0.0128, paired t-test). Maximum plasma glucose elevation over baseline was 117 mg*dl−1 and 20 mg*dl−1 after oral glucose or ENSO 16, respectively. Insulin and C-peptide AUC0−180 min were significantly greater after glucose compared to ENSO 16 intake (p < 0.01, Wilcoxon rank sum test). The mean maximal concentrations of plasma glucose, insulin and C-peptide after glucose intake were 1.5, 4.6 and 2.7-fold greater after glucose intake compared to ENSO 16 intake, respectively. Adverse reactions were mostly mild and not different between treatments. Conclusion. ENSO 16 has only a small impact on plasma glucose metabolism. This may be of interest in a dietary context and may help to reduce calory intake.Trail registration NCT05457400. First registration: 14/07/2022. https://clinicaltrials.gov/study/NCT05457400.