Diabetes

Diabetes is a chronic disease in which the body is unable to produce sufficient insulin or effectively use the insulin it produces. As a result, the body cannot properly metabolize sugar (glucose) in the blood. This results in hyperglycemia, or elevated blood levels of glucose. Glucose comes from food starch (found in such foods as potatoes, grains, rice, sugar) and from the liver, which puts stored sugar (called glycogen) into blood. Insulin, a hormone produced by the pancreas, helps break down (metabolize) glucose by allowing it to enter cells, where it is used as fuel.

Diabetes is a common condition, affecting approximately 3 in every 100 people. It is rare in infants, but commonly develops as people get older.¹

Are there different types of diabetes?

There are two primary types of diabetes mellitus, Type I diabetes (also known as insulin-dependent or juvenile diabetes) and Type II diabetes (also known as adult-onset diabetes). There is also a type of temporary diabetes known as gestational diabetes that affects pregnant women or women who have just given birth.

Type I (insulin-dependent) diabetes

Affecting between 5 and 10 percent of all diagnosed cases of diabetes², Type I typically appears in people under the age of 40 whose bodies are unable to produce insulin. More specifically, insulin-dependent diabetes develops when cells in the pancreas responsible for the production of insulin have been destroyed. It's unclear just why these cells become damaged, but it's believed this may be the result of an abnormal autoimmune response by the body, perhaps triggered by a viral or other type of infection.³ In some genetically predisposed people, the "trigger" stimulates an immune attack against the beta cells in the pancreas, the cells that produce insulin.⁴ Risk factors are less well defined for Type I diabetes than for Type II diabetes, but genetic and environmental factors are involved in the development of Type I diabetes.⁵

Type I diabetes generally affects younger people. Onset of insulin-dependent diabetes is very quick, usually over the span of a few weeks and symptoms are typically very obvious. This type of diabetes is treated by insulin injections, diet, and regular exercise.

Type II (adult-onset or maturity-onset) diabetes

Affecting between 90 and 95 percent of all diagnosed cases of diabetes⁶, Type II diabetes, often called adult-onset or maturity-onset diabetes because it affects people in middle age, develops when a person's body is still able to produce insulin. However, insulin produced by the pancreas is either insufficient or it does not properly metabolize glucose.

Onset of Type II diabetes is slow, and the symptoms are usually less severe than in Type I. In fact, some people may notice no symptoms at all and are only diagnosed following a routine medical exam. As mentioned above, diabetes mellitus Type II typically affects people over the age of 40, although it is common among younger people, particularly those of Asian or Afro-Caribbean descent.⁷ Hispanic/Latino people and Native Americans/First Nations people are also at increased risk.⁸

Those most at risk of developing Type II diabetes are:

• people with a family history of diabetes
• women with a prior history of gestational diabetes
• people with impaired glucose tolerance
• people with a sedentary lifestyle
• people between 40 and 75—it's estimated that of all people affected by diabetes, approximately 75 percent have Type II diabetes. Risk increases with age.
• people of Asian or Afro-Caribbean descent and Native Americans/First Nations people are 3 to 5 times more likely to develop diabetes than Caucasians.
• people who are very overweight—over 80 percent of people with Type II diabetes are overweight. The more overweight you are—and especially if you carry your weight around your waist rather than around your hips and buttocks—the higher your risk
• women who have given birth to a large baby (over 9 pounds or 4 kilos)—pregnant women may develop a temporary type of diabetes known as gestational diabetes (see below). Gestational diabetes—or giving birth to a large baby—can each increase a woman's risk of developing Type II diabetes.

Gestational diabetes

A third type of diabetes, gestational diabetes, develops in 2 to 5 percent of all pregnancies and usually disappears when pregnancy is over. Gestational diabetes is more common among Blacks, Hispanics/Latinos, and Native American/First Nations women and in women with a family history of diabetes. Obese women are also at increased risk of developing gestational diabetes. Women who have had gestational diabetes and women who have given birth to a large baby (over 9 pounds or 4 kilos) are at increased risk of developing Type II diabetes. Some studies have shown that nearly 40 percent of women with a history of gestational diabetes later developed diabetes. What's more, children born of women who have had gestational diaetes are at increased risk for developing Type II diabetes later in life.⁹

There are other types of specific diabetes, but these are very rare, accounting for 1 to 2 percent of all diagnosed cases of diabetes. These rare types of diabetes may be caused by genetic syndromes, surgery, drugs, malnutrition, infections, and other illnesses.¹⁰

What are the signs and symptoms of diabetes?

Signs and symptoms of diabetes include:

• increased thirst
• frequent urination, particularly at night
• extreme fatigue
• tingling or numbness in the hands and feet
• unexplained weight loss
• genital itching, or regular episodes of thrush
• blurred vision or sudden changes in vision
• very dry skin or itchy skin
• sores that are slow to heal
• more infections than usual

Nausea, vomiting, or stomach pains may accompany some of the above symptoms in the abrupt onset of Type I (insulin-dependent) diabetes. In Type II diabetes, however, symptoms may not always be easily recognized.¹¹

The importance of early diagnosis

Sadly, too many people develop diabetes-related complications because their diabetes is diagnosed too late. What makes diabetes a serious disease is the impact it can have on other parts of the body. Unfortunately, by the time many adults are diagnosed with diabetes, many of the complications of the disease have already begun to manifest: blindness or diabetic retinopathy, kidney failure, heart disease, stroke, and nerve damage that can lead to amputation.¹²

If you exhibit any of the symptoms of diabetes, and even if you don't — if you suspect you may have diabetes, take preventative measures now. Early diagnosis and treatment can significantly reduce the risk of developing serious complications. A simple blood test can determine whether you have diabetes.

What if I have diabetes? How is diabetes treated? Is there a cure?

At present, there is no known cure for diabetes, but much work is being done in advancing knowledge, treatment, and prevention strategies. People with diabetes can lead full and productive lives. Training in self-management of diabetes is essential, and treatments must be tailored to psychosocial, medical, and lifestyle issues of the individual. Common to all treatment programs, however, is the goal of maintaining blood pressure and blood glucose levels as close to normal as possible at all times. Treatment and a healthy lifestyle will help improve a patient's overall well-being and protect against long-term damage to the eyes (see What is diabetic retinopathy?), kidneys, nerves, heart and major arteries.¹³

Treating Type I Diabetes

Because in Type I diabetes, the pancreas fails to produce insulin, Type I diabetes is particularly difficult to control. Treatment requires a carefully calculated diet, planned physical activity, home blood glucose monitoring several times a day, and multiple daily insulin injections.¹⁴

Treating Type II Diabetes

Treatment of Type II diabetes typically includes controlling one's diet, exercise, home blood glucose monitoring several times a day, and in some cases, oral medication and/or insulin. Approximately 40 percent of patients with Type II diabetes require insulin injections.¹⁵

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1. Who gets diabetes and what causes it? Diabetes UK. 2000.
2. Frequently Asked Questions. Diabetes Public Health Resource. National Center for Chronic Disease Prevention and Health Promotion. United States Department of Health and Human Services. 2004.
3. Who gets diabetes and what causes it? Diabetes UK. 2000.
4. Frequently Asked Questions. Diabetes Public Health Resource. National Center for Chronic Disease Prevention and Health Promotion. United States Department of Health and Human Services. 2004.
5. Frequently Asked Questions. Diabetes Public Health Resource. National Center for Chronic Disease Prevention and Health Promotion. United States Department of Health and Human Services. 2004.
6. Frequently Asked Questions. Diabetes Public Health Resource. National Center for Chronic Disease Prevention and Health Promotion. United States Department of Health and Human Services. 2004.
7. Understanding Diabetes. Diabetes UK. 2000.
8. Frequently Asked Questions. Diabetes Public Health Resource. National Center for Chronic Disease Prevention and Health Promotion. United States Department of Health and Human Services. 2004.
9. Frequently Asked Questions. Diabetes Public Health Resource. National Center for Chronic Disease Prevention and Health Promotion. United States Department of Health and Human Services. 2004.
10. Frequently Asked Questions. Diabetes Public Health Resource. National Center for Chronic Disease Prevention and Health Promotion. United States Department of Health and Human Services. 2004.
11. Frequently Asked Questions. Diabetes Public Health Resource. National Center for Chronic Disease Prevention and Health Promotion. United States Department of Health and Human Services. 2004.
12. Are you at risk for diabetes? Diabetes UK. 2000.
13. Understanding Diabetes. Diabetes UK. 2000.
14. Frequently Asked Questions. Diabetes Public Health Resource. National Center for Chronic Disease Prevention and Health Promotion. United States Department of Health and Human Services. 2004.
15. Frequently Asked Questions. Diabetes Public Health Resource. National Center for Chronic Disease Prevention and Health Promotion. United States Department of Health and Human Services. 2004.