Regulation of glucose levels in the blood is very important
Normal Fasting (Serum) ~ 70 – 100 mg/dl
Elevated = Diabetes
Low = Hypoglycemia
Insulin from pancreas stimulates uptake of glucose into muscle cells by activating the GLUT4 transporter. When serum levels of glucose decrease too much, then the pancreas releases glucagon to stimulate the liver and kidney to break down glycogen to glucose and release glucose into the blood (glycogenolysis). Adrenals will release cortisol if levels stay too low to enhance breakdown of protein in muscles to release amino acids so the liver can pick up the amino acids and make them into glucose (gluconeogenesis).
From the carbohydrate/diet standpoint, after eating a meal, glucose levels increase in the blood and trigger an insulin response. Chronic increases in insulin can greatly increase the risk for developing Type II diabetes. Eating foods that produce a large increase in insulin tend to be more risky for diabetes than eating foods that do not stimulate a large increase in glucose levels.