RESULTS
Thirty-six participants (22 women and 14 men) completed the study. There was no significant difference in BMI (P = 0.29) on the meal test days (Table 1). Similarly, no significant differences were observed for fasting plasma glucose (P = 0.42), serum insulin (P = 0.42), serum C-peptide, and EE (P = 0.30) before the consumption of the 3 meals.
Maximum increases in insulin concentration and iAUC for serum insulin (Figure 3) were heterogeneous (P =
0.0008) after the 3 meals: these measures were 36% and 32% lower, respectively, after consumption of the CAC meal than after that of the BAB meal. The maximum increases in insulin concentration and iAUC for serum insulin after the CAB meal were in between but closer to those with the CAC meal than with the BAB meal. The maximum increases in insulin concentration and iAUC for serum insulin after the CAB meal were 15% (P = 0.074) and 17% (P = 0.072) lower, respec- tively, than after the BAB meal. The maximum increases in insulin concentration and iAUC for serum insulin after the CAC meal were 24% (P = 0.24) and 18% (P = 0.52) lower, respec- tively, than after the CAB meal. The maximum increases in C-peptide concentration and iAUC for C-peptide were not sig- nificantly different between the 3 meals (Table 2). There was no significant difference (P = 0.1) in EE (Figure 4) or in the respi- ratory quotient between the 3 meals (Table 2).
The analysis showed that the significant heterogeneity observed between the 3 meals in the whole group came predom- inantly from the subjects with a BMI > 26.3 (Table 3). In addition to these results, subjects with a BMI > 26.3 showed significant heterogeneity (P < 0.02 for all) in maximum C-peptide, iAUC C-peptide, iAUC C-peptide/insulin quotient, and net AUC EE. Postestimation analysis showed a higher C- peptide/insulin quotient, and a lower net EE after the CAB meal (P < 0.045 for both) and the CAC meal (P < 0.003 for both) than after the BAB meal. The maximal change in C-peptide was smaller with the CAC meal than with the CAB and the BAB meals (P < 0.02 for both), and iAUC C-peptide was lower after the CAC meal than after the BAB meal (P = 0.015).