Comparison of Plasma Glucose and Insulin Responses to Mixed Meals of High-, Intermediate-, and Low-Glycemic Potential

Abstract

Although plasma glucose and insulin responses have been shown to vary considerably when either normal subjects or patients with non-insulin-dependent diabetes mellitus (NIDDM) consume different carbohydrate-rich foods, it has been difficult to demonstrate this phenomenon when the same foods have been incorporated into a single mixed meal. To pursue this issue further, plasma glucose and insulin concentrations were determined at hourly intervals from 0800 to 2100 h in NIDDM patients in response to three meals (breakfast, lunch, and dinner) calculated to be of low-, intermediate-, and high-glycemic potency. The total integrated glucose response (mean ± SE) during the day the low-glycemic meals were ingested was ∼7% lower (2500 ± 246 mg · dl⁻¹ · h⁻¹) than on the days patients ate either the intermediate- (2701 ± 280 mg · dl⁻¹ · h⁻¹) or high- (2718 ± 311 mg · dl⁻¹ · h⁻¹) glycemic meals. When these data were analyzed by meal, it became apparent that the plasma glucose response to breakfast and dinner were essentially identical after consumption of the meals of either low-, intermediate-, or high-glycemic potency. Thus, the modest attenuation of the day-long glycemic response on the day patients ate the lowglycemic meal was due to a reduction in plasma glucose concentration after lunch. The day-long plasma insulin responses to the meals of different glycemic potency were qualitatively similar.