This study investigated the effects of food temperature on glucose-regulating hormones in normal subjects and patients with type 2 diabetes. Both groups underwent oral glucose tolerance tests (OGTTs) with hot (50°C) and cold (8°C) glucose solutions on separate days. Blood glucose, insulin, GIP, GLP-1, and cortisol were measured. Hot OGTTs resulted in significantly higher blood glucose in both groups. However, higher insulin and GLP-1 levels after hot OGTTs were only observed in normal subjects. Continuous glucose monitoring (CGM) revealed higher 24-hour mean glucose in both groups with hot meals, and higher standard deviation of mean blood glucose in normal subjects only. These findings suggest that food temperature significantly influences glucose absorption and GLP-1 response, an effect lost in type 2 diabetes.

Yun Hu, Peng Zhang, Bo Ding, Xin Cao, Yi Zhong, Kok-Onn Lee, Jian-Hua Ma