Fig. 5: Intestinal concentrations of starch digestion products, estimated undigested starch contents and their relationship with blood responses.
a, Time-series and average concentrations for gastric maltose. Connected data points in bar charts are from the same individual. Data show mean ± s.e.m., n = 9. b, Time-series and average concentrations for duodenal maltose. Connected data points are from the same individual. Data show mean ± s.e.m., n = 9. c, Time-series and average concentrations for gastric glucose. Connected data points are from the same individual. Data show mean ± s.e.m., n = 9. d, Time-series and average concentrations for duodenal glucose. Connected data points are from the same individual. Data show mean with s.e.m., n = 9. e, Time-series and average concentrations for duodenal undigested starch expressed as a proportion of ‘total pellet sugars’. Connected data points are from the same individual. Data show mean ± s.e.m., n = 9. f, Time-series and average concentrations for duodenal undigested starch calculated from the aspirated solid content and its pellet composition. Data shows mean with s.e.m., n = 9. g, Spearman correlations of 0–30 min delta changes in gastric maltose (mg ml−1) with blood glucose (mmol l−1), GIP (pg ml−1) and GLP-1 (pmol l−1). The scatter-plot displayed individual points with a regression line representing the mean predicted values and shaded bands representing 95% CI (n = 9). BldGlu, blood glucose. h, Spearman correlations of undigested starch in duodenal aspirates with PYY iAUC pmol l−1 × (0–180 min), GLP-1 iAUC pmol l−1 × (30–180 min) and GIP iAUC pg ml−1 × (30–180 min). The scatter-plot displayed individual points with a regression line representing the mean predicted values and shaded bands representing 95% CI (n = 9). For bar charts ABCD, one-way RM ANOVA showed significant main effects for gastric maltose (P = 0.006), gastric glucose (P = 0.002), duodenal maltose (P = 0.020) and duodenal glucose (P = 0.003) and annotations are the result of two-sided post hoc pairwise comparisons; Tukey’s multiplicity adj. P values were *P < 0.05, **P < 0.01, ****P < 0.001. For scatter-plot (EF), two-sided Spearman correlation tests showed that gastric maltose was significantly correlated with blood glucose (R = 0.64, P = 0.004), GIP (R = 0.47, P = 0.014) and GLP-1 (R = 0.42, P = 0.034). Duodenal undigested starch was significantly associated with PYY iAUC (0–180 min) (R = 0.39, P = 0.048), GLP-1 iAUC (30–180 min) (R = 0.60, P < 0.001) and GIP iAUC (30–180 min) (R = 0.62, P < 0.001).
