Humans need a minimum level of glucose in their blood at all times to function and stay alive. Insulin is a peptide hormone naturally secreted by the pancreas to regulate the body's management of glucose. When a healthy individual begins a meal, the pancreas releases a natural spike of insulin, called the first-phase insulin release, which is critical to the body's overall control of glucose. Many patients with diabetes lack the first-phase insulin release and must treat themselves with daily meal-time insulin injections to avoid the negative effects of hyperglycemia and hypoglycemia. The following graph illustrates the first phase insulin release in a healthy individual as compared to an individual with Type 2 diabetes:
The long-term adverse effects of too much glucose in the blood stream (hyperglycemia) include blindness, loss of kidney function, nerve damage and loss of sensation and poor circulation in the periphery, which in more severe cases, may lead to amputations. Too little glucose in the blood stream (hypoglycemia) can be a more immediate threat and result in many diabetic emergency room visits. Consequences of hypoglycemia include dizziness, fainting, loss of mental acuity, confusion, increased heart rate and hunger. At very low blood glucose levels, hypoglycemia can result in loss of consciousness, coma and even death. According to the American Diabetes Association (ADA), insulin-using patients with diabetes have on average 1.2 serious hypoglycemic events per year, many of which require hospital emergency room visits by the patients.