Glycemic Variations after Ingestion of Different Carbohydrate-Containing Foods Assessed by Continuous Glucose Monitoring in Healthy and Diabetic Individuals in Daily Life

Abstract

Carbohydrate counting is a meal planning approach for diabetic patients, but individual variations of the effect of glycemic index do not seem to be well taken into account. Here we assessed glycemic variations after the ingestion of different carbohydrate-containing foods by continuous glucose monitoring in healthy and diabetic individuals in daily life. After an overnight fast, seven healthy persons and four patients each of type 1 and 2 diabetes were instructed to eat three different kinds of 40 g carbohydrate-containing breakfast within 10 minutes for three consecutive days. The meals consisting of foods chosen from starchy foods, fruits and dairy foods were 100 g cooked rice with Japanese green tea seasoning (183 kcal), 300 g apple (162 kcal), and 35 g cereal with 180 ml milk (253 kcal), respectively. The glycemic profiles were measured every 5 minutes over three hours before and after the breakfast meals by using
a continuous glucose monitoring system (iPro2®). Sulfonylurea was not taken, and insulin dose was reduced at the breakfast to avoid hypoglycemia, which was fixed during the study. The respective profiles of glycemic responses to the breakfast meals varied largely among individuals, especially in diabetic patients. The sums of glycemic increments over three hours after the ingestion of apple and cereal+milk (322 ± 123 (mean ± SD) and 181 ± 275 mg/dl) were significant (p<0.05) lower than those after the rice ingestion (543 ± 209 mg/dl) in healthy persons, but there was no significant difference among those (528 ± 471, 766 ± 1374 and 1442 ± 1025 mg/dl, respectively) in diabetic patients. Postprandial glucose levels were suppressed in the cereal+milk meal, but the elevated glucose levels appeared to persist in patients with type 1 diabetes. Medical staff should be aware of controlling carbohydrate intake with glycemic index, keeping in mind large individual variations of glycemic responses to the same amount of carbohydrate. It may be wise for diabetic patients to develop their own personal glycemic indexes in their respective situations.