A Web-Based Educational Simulation Package for Glucose-Insulin Levels in the Human Body

"The simulator does not differentiate between people regarding their sex, age, race, or BMI (body mass index); instead it represents an average person. Also, GlucoSim does not take into account intra- and inter-personal variations and it should not be used for making medical decisions."
The GlucoSim should only be used for educational purposes.

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Process of food metabolism
How is diabetes diagnosed ?
Types of diabetes
Incidence and risk factors
Tests for diabetes
Diabetes Management
Role of health care provider


Process of food metabolism

To understand diabetes, it is important to first understand the normal process of food metabolism. Several things happen when food is digested:

  • A sugar called glucose enters the bloodstream. Glucose is a source of fuel for the body.
  • An organ called the pancreas makes insulin and secretes it into the bloodstream. Production and secretion of insulin is triggered by increase in glucose concentration in bloodstream. The role of insulin is to move glucose from the bloodstream into muscle, fat, and liver cells, where it can be used as fuel. As glucose concentration in bloodstream is reduced production and secretion of insulin is reduced as well.
  • When the body produces enough insulin and functions properly, glucose levels in the bloodstream and cells are controlled automatically. The glucose in the bloodstream stays within a safe range, never getting too high or too low. When the supply of glucose is not maintained the body's glucose levels can either become too high (hyperglycemia) or too low (hypoglycemia).
  • In a healthy person who does not have diabetes, normal levels of glucose concentration in blood are typically 70-110 mg/dL (milligrams per deciliter) before a meal and less than 120 mg/dl two hours after a meal. Typical glucose concentration for hypoglycemia range from the high/mid 60's (mg/dl) and dip into the lower 40's (mg/dl). Typical glucose concentrations for hyperglycemia are greater than 120 mg/dL .
  • Hypoglycemia is usually caused by an overdose of insulin or some other disease process that causes increase amount of circulating insulin. Symptoms of hypoglycemia usually occur when blood glucose levels fall to 40 mg/dL or lower.

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    How is diabetes diagnosed ?

    The fasting blood glucose test is one way to diagnose diabetes: it is easy to perform and is convenient. After the person has fasted overnight (at least 8 hours), a sample of blood is drawn and analyzed.

  • Normal fasting glucose levels are between 90- 110 milligrams per deciliter (mg/dl) (milligrams per deciliter). Fasting plasma glucose levels of more than 126 mg/dl on two or more tests on different days indicate high probability of diabetes.
  • Fasting hyperglycemia is defined as a blood sugar greater than 90-130 mg/dL after fasting for at least 8 hours.
  • In people without diabetes post meal sugars will sometimes go over 140 mg/dL but occasional, after a large meal, a 1-2 hour post-meal glucose level can reach 180 mg/dL. Consistently elevated high post-meal glucose levels can be an indicator that a person is at high risk for developing type 2 diabetes

    The oral glucose test is another diagnostic test. A person who has fasted overnight drinks a glassful of glucose solution. Blood samples are drawn periodically and glucose concentration in blood is measured. Trends in glucose concentration variations over a period of time, maximum concentration value, the speed of concentration drop over time to the fasting glucose level are interpreted to assess if the person has diabetes.

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    Diabetes is a life-long disease marked by high levels of sugar in the blood. It can be caused by too little insulin (a hormone produced by the pancreas to regulate blood sugar), resistance to insulin, or both.

    People with diabetes have high blood glucose. This is because their pancreas does not make enough insulin or their muscle, fat, and liver cells do not respond to insulin normally, or both.

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    Types of diabetes

    There are three major types of diabetes:

  • Type 1 diabetes is usually diagnosed in childhood. The body makes little or no insulin, and daily injections of insulin are required to sustain life. Without proper daily management, medical emergencies can arise.
  • Type 2 diabetes is far more common than type 1 and makes up 90% or more of all cases of diabetes. It usually occurs in adulthood. Here, the pancreas does not make enough insulin to keep blood glucose levels normal, often because the body does not respond well to the insulin. Many people with type 2 diabetes do not know they have it, although it is a serious condition. Type 2 diabetes is becoming more common due to the growing number of older Americans, increasing obesity, and failure to exercise.
  • Gestational diabetes is high blood glucose that develops at any time during pregnancy in a person who does not have diabetes.

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    Both hereditary and environmental factors lead to its development and progression.

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    Incidence and risk factors

    Diabetes affects about 17 million Americans. There are many risk factors for diabetes, including:

  • A parent, brother, or sister with diabetes
  • Obesity
  • Age greater than 45 years
  • Some ethnic groups (particularly African-Americans and Hispanic Americans)
  • Gestational diabetes or delivering a baby weighing more than 9 pounds
  • High blood pressure High blood levels of triglycerides (a type of fat molecule)
  • High blood cholesterol level

    The American Diabetes Association recommends that all adults be screened for diabetes at least every three years. A person at high risk should be screened more often.

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    High blood levels of glucose can cause several problems, including frequent urination, excessive thirst, hunger, fatigue, weight loss, and blurry vision. However, because type 2 diabetes develops slowly, some people with high blood sugar experience no symptoms at all.

    Symptoms of type 1 diabetes:

  • Increased thirst
  • Increased urination
  • Weight loss in spite of increased appetite
  • Fatigue
  • Nausea
  • Vomiting

    Symptoms of type 2 diabetes:

  • Increased thirst
  • Increased urination
  • Increased appetite
  • Fatigue
  • Blurred vision
  • Slow-healing infections
  • Impotence in men

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    Tests for diabetes

    Self testing

    Self-monitoring of blood glucose is done by checking the glucose content of a drop of blood. Regular testing tells you how well diet, medication, and exercise are working together to control your diabetes.

    The results of the test can be used to adjust meals, activity, or medications to keep blood sugar levels in an appropriate range. Testing provides valuable information for the health care provider and identifies high and low blood sugar levels before serious problems develop.

    The American Diabetes Association recommends that pre-meal blood sugar levels fall in the range of 80 to 120 mg/dL and bedtime blood levels fall in the range of 100 to 140 mg/dL. Your doctor may adjust this depending on your circumstances.

    You should also ask your doctor how often to check your hemoglobin A1c (HbA1c) level. The HbA1c is a measure of average blood glucose during the previous two to three months. It is a very helpful way to monitor a patient's overall response to diabetes treatment over time. A person without diabetes has an HbA1c around 5%. People with diabetes should try to keep it below 7%.

    Ketone testing is another test that is used in type 1 diabetes. Ketones build up in the blood when there is not enough insulin in people with type 1diabetes, eventually "spilling over" into the urine. The ketone test is done on a urine sample. High levels of blood ketones may result in a serious condition called ketoacidosis. Ketone testing is usually done at the following times:

  • When the blood sugar is higher than 240 mg/dL
  • During acute illness (for example, pneumonia, heart attack, or stroke)
  • When nausea or vomiting occur
  • During pregnancy

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    There is no widespread cure for diabetes. The immediate goals are to stabilize your blood sugar and eliminate the symptoms of high blood sugar. The long-term goals of treatment are to prolong life, relieve symptoms, and prevent long-term complications such as heart disease, blindness, and kidney failure.

    A Cure for diabetes can be achieved by pancreas transplantation or islet cell transplantation. Islet cells are the cells that produce insulin in the pancreas. Pancreas transplantation is a high-risk medical procedure. Islet cell transplantation has a lower medical risk. Limited supply of donor pancreas (organs are harvested from people who die prematurely) and the reaction of the human body to transplanted organs severely affect the cure by transplant surgery.


    Insulin is injected into the fatty tissue just under the skin. It also can be given through an insulin pump or a device that sprays the medication into the skin (jet injector). Once an individual overcomes his or her initial anxiety, giving yourself a shot will become part of your daily routine .

    Medications to treat diabetes include insulin and glucose-lowering pills, called oral hypoglycemic agents. The bodies of people with type 1 diabetes cannot make their own insulin, so daily insulin injections are required. The bodies of people with type 2 diabetes make insulin but cannot use it effectively.

    Insulin is not available in oral form yet. It is delivered to the body by injections that are generally required one to four times per day. Some people use an insulin pump, which is worn at all times and delivers a steady flow of insulin throughout the day. Oral insulin capsules and nasal insulin sprays are currently undergoing medical trials and may become available for public use in the near future.

    People who need insulin are taught to give themselves injections by their health care providers or diabetes educators.

  • Unlike type 1 diabetes, type 2 diabetes may respond to treatment with exercise, diet, and/or oral medications.

    Gestational diabetes is treated with diet and insulin.

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    Emergency complications include diabetic hyperglycemic hyperosmolar coma.

    For individuals who are hypoglycemic and cannot respond their brain’s request by eating something to raise blood glucose, most patients progress to neuro-glyco-penic ranges (the brain is not getting enough glucose). At this point, symptoms advance to confusion, drowsiness, changes in behavior, coma and seizure.

    Long-term complications include:

  • Diabetic retinopathy -involving retina and other parts of eye
  • Diabetic nephropathy -involving kidneys
  • Diabetic neuropathy -involving nerves
  • Peripheral vascular disease -involving blood vessels

    Hyperlipidemia, hypertension, atherosclerosis-involving heart.

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    Diabetes management

    Basic diabetes management skills will help prevent the need for emergency care. These skills include:

  • How to recognize and treat low blood sugar (hypoglycemia) and high blood sugar (hyperglycemia)
  • What to eat and when
  • How to take insulin or oral medication
  • How to test and record blood glucose
  • How to test urine for ketones (type 1 diabetes only)
  • How to adjust insulin and/or food intake when changing exercise and eating habits
  • How to handle sick days
  • Where to buy diabetes supplies and how to store them

    One should work closely with your health care provider to learn how much fat, protein, and carbohydrates you need in your diet. The specific meal plans need to be tailored to your food habits and preferences

    People with type 1 diabetes should eat at about the same times each day and try to be consistent with the types of food they choose. This helps to prevent blood sugars from becoming extremely high or low.

    Type 2 diabetics should follow a well-balanced and low-fat diet.

    Weight management is important to achieving control of diabetes. Some people with type 2 diabetes can stop medications after losing excess weight, although the diabetes is still present.


    Regular exercise is especially important for people with diabetes. It helps with blood sugar control, weight loss, and high blood pressure.

    People with diabetes who exercise are less likely to experience a heart attack or stroke than diabetics who do not exercise regularly.

    A patient should be evaluated by his physician before starting an exercise program.

    Here are some exercise considerations:

  • Choose an enjoyable physical activity that is appropriate for your current fitness level.
  • Exercise every day, and at the same time of day, if possible.
  • Monitor blood glucose levels before and after exercise.
  • Carry food that contains a fast-acting carbohydrate in case you become hypoglycemic during or after exercise.
  • Carry a diabetes identification card and a mobile phone or change for a payphone in case of emergency.
  • Drink extra fluids that do not contain sugar before, during, and after exercise.
  • Changes in exercise intensity or duration may require changes in diet or medication dose to keep blood sugar levels from going too high or low.


    People with diabetes are prone to foot problems because of the likelihood of damage to blood vessels and nerves and a decreased ability to fight infection. Problems with blood flow and damage to nerves may cause an injury to the foot to go unnoticed until infection develops. Death of skin and other tissue can occur.

    If left untreated, the affected foot may need to be amputated. Diabetes is the most common condition leading to amputations.

    To prevent injury to the feet, people with diabetes should adopt a daily routine of checking and caring for the feet as follows:

  • Check your feet every day, and report sores or changes and signs of infection.
  • Wash your feet every day with lukewarm water and mild soap, and dry them thoroughly.
  • Soften dry skin with lotion or petroleum jelly.
  • Protect feet with comfortable, well-fitting shoes.
  • Exercise daily to promote good circulation.
  • See a podiatrist for foot problems or to have corns or calluses removed.
  • Remove shoes and socks during a visit to your health care provider and remind him or her to examine your feet.
  • Stop smoking, which hinders blood flow to the feet.
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    Role of health care provider

    Go to the emergency room or call the local emergency number (such as 911) if symptoms of ketoacidosis occur:

  • Increased thirst and urination
  • Nausea
  • Deep and rapid breathing
  • Abdominal pain
  • Sweet-smelling breath
  • Loss of consciousness

    Go to the emergency room or call the local emergency number if symptoms of extremely low blood sugar (hypoglycemic coma or severe insulin reaction) occur:

  • Weakness
  • Drowsiness
  • Headache
  • Confusion
  • Dizziness
  • Double vision
  • Lack of coordination
  • Convulsions or unconsciousness.

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    Maintaining an ideal body weight and an active lifestyle may prevent the onset of type 2 diabetes. Currently there is no way to prevent type 1 diabetes.

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