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NutrInsight • Slow-release carbohydrates: Growing evidence on metabolic responses and public health interest

Figure 12: Individual 24-h glucose monitoring records (mean of 2 days) from 21 healthy subjects.
Source: Christiansen, 2006

3.2 From normal glycemia to hyperglycemia

The glycemic response is a closely regulated physiological parameter that involves several organs and tissues.
Both genetic susceptibility (family history) and lifestyle factors (e.g. level of physical activity and type of diet)
influence the regulation of the glycemic response. Progression from normal glycemia to type 2 diabetes involves
three main steps of impairment of glycemic control. First, there is a concomitant decrease in glucose-induced
insulin secretion and a reduced tissue response to insulin because of insulin resistance, which leads to higher
postprandial hyperglycemic phases. In a later stage, there is an increase in hepatic glucose secretion (mainly
during fasting stages), which leads to an elevated fasting blood glucose level. At the end, beta-cell function is
impaired during hyperglycemic phases, which is part of the type 2 diabetes genesis (see Figure 13).

Normal Glycemia Impaired Glycemic Control Type 2 Diabetes
Genetic
Susceptibility Insulin Lipolysis Impaired
De ciency Fat Oxidation, & ß-cell

Glucose-induced Hepatic function
Insulin Secretion Glucose
Secretion Hyperglycemia

Lifestyle Tissue Response Cellular Glucose Hyper-
Factors To Insulin Glucose Transport insulinemia
Uptake
Insulin
Resistance

Figure 13 : Conceptual model for the development of type 2 diabetes.
Source: Adapted from LaMonte et al., 2005

Thus, the glycemic response reflects the body’s ability to adapt itself to the arrival of exogenous carbohydrates.
Based on data presented by Dr. Vinoy and Prof. Laville, the modulation of postprandial glycemic response
can be obtained very interestingly by the rate of digestibility of the carbohydrates included in the diet.

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