Background: A sequential response of insulin secretion is likely to follow the sequential pattern of digestion to optimize the effect of insulin and other counter regulatory peptides on the target tissues to maintain optimum insulin signaling pathway activation. Therefore, it is likely to relate insulin secretory response to the corresponding phase of digestion.

Patients and methods: Plasma glucose, insulin and glucagon levels of three groups, each comprises of 10 persons. Group “N” for normal, group “P” for pre-diabetic and group “D” for type 2 diabetes individuals. Fluctuations in insulin secretion, in relation to changes of plasma glucose levels throughout the four phases of digestion will be traced, changes in glucagon levels will be also evaluated.

Results: Early in the gastric-filling phase insulin was decreasing while glucose was rising, whereas, early in the gastric-emptying phase, insulin was rising while glucose was decreasing. Statistical significance of glucagon changes was higher than that of insulin between groups.

Conclusion: Factors, which regulate insulin secretion during the gastric-filling phase, may differ than those during the gastric emptying-phase. Insulin/Glucagon ratio, is more contributed, than insulin alone, to the metabolic abnormalities associated with diabetes. It is more informative to consider insulin secretion in relation to the corresponding phase of digestion. Therefore, a four- phase cycle of insulin secretion may be suggested.