Protein hydrolysate co-ingestion does not modulate 24 h glycemic control in long-standing type 2 diabetes patients

Objective: Evaluate the efficacy of protein hydrolysate co-ingestion as a dietary strategy to improve blood glucose homeostasis under free-living conditions in long-standing type 2 diabetes patients. Methods: A total of 13 type 2 diabetes patients were enrolled in a randomized, double-blind cross-over design and studied on two occasions for 40 h under strict dietary standardization but otherwise normal, free-living conditions. In one trial, subjects ingested a protein hydrolysate (0.4 g kg-1 bw casein hydrolysate, PRO) with every main meal. In the other trial, a placebo was ingested (PLA). Blood glucose concentrations were assessed by continuous glucose monitoring. Results: Average 24 h glucose concentrations were similar between the PLA and the PRO trials (8.9+/-0.8 vs 9.2+/-0.7 mmol l-1, respectively). Hyperglycemia (glucose concentrations >10 mmol l-1) was experienced 34+/-9% of the time (8+/-2 h per 24 h) in the PLA trial. Protein hydrolysate co-ingestion with each main meal (PRO) did not reduce the prevalence of hyperglycemia (39+/-10%, 9+/-2 h per 24 h; P=0.2). Conclusion: Co-ingestion of a protein hydrolysate with each main meal does not improve glucose homeostasis over a 24 h period in long-standing type 2 diabetes patients.