(CNN) -- Here's a look at diabetes, a disease that affects millions of people in the U.S. Diabetes is a disease that affects millions of people in the U.S. It is characterized by high levels of blood glucose resulting from defects in insulin production, insulin action, or both. The disease can lead to serious complications such as blindness, kidney damage, cardiovascular disease, limb amputations and premature death.
There are several types of diabetes: Type 1, Type 2, and gestational diabetes.
Prediabetes occurs when blood glucose levels are higher than normal but not yet high enough to be diagnosed as diabetes. Before developing Type 2 diabetes, people almost always have prediabetes. Research has shown that some long-term damage to the body may occur during prediabetes.
Type 1 diabetes develops when the body's immune system destroys pancreatic beta cells, the only cells in the body that make insulin. This form of diabetes usually strikes children and young adults. Only 5-10% of people with diabetes have Type 1. Risk factors for Type 1 diabetes may be autoimmune, genetic, or environmental. There is no known way to prevent Type 1 diabetes.
Type 2 diabetes occurs when the body does not produce enough insulin or the cells do not use insulin properly. Type 2 diabetes is the most common form of diabetes and in adults, it accounts for about 90% to 95% of all diagnosed cases of diabetes. It is associated with older age, obesity, family history, physical inactivity, and race/ethnicity. It is more common in African Americans, Latino Americans, American Indians, and Asian Americans, Native Hawaiians and other Pacific Islanders. Type 2 diabetes in children and adolescents, although still rare, is being diagnosed more frequently.
Gestational diabetes is a form of glucose intolerance diagnosed during pregnancy. It affects about 4% of all pregnant women. A diagnosis of gestational diabetes doesn't mean that a woman had diabetes before she conceived, or that she will have diabetes after giving birth.
Other types of diabetes result from genetic conditions, surgery, medications, infections and other illnesses. Such types of diabetes account for 1% to 5% of all diagnosed cases.
Possible Symptoms: Frequent urination
Unexplained weight loss
Sudden changes in vision
Numbness in hands or feet
Slow healing wounds
Complications: Adults with diabetes have heart disease death rates about two to four times higher than adults without diabetes.
The risk for stroke is two to four times higher among people with diabetes.
People with diabetes are at high risk for high blood pressure
Diabetes is the leading cause of new cases of blindness among adults aged 20-74 years.
Diabetes is the leading cause of kidney failure.
About 60% of people with diabetes have mild to severe forms of nervous system damage or neuropathy.
More than 60% of non-traumatic lower-limb amputations occur on people with diabetes.
U.S. Diabetes Statistics: An estimated 86 million people 20 or older have pre-diabetes.
21 million people have been diagnosed with diabetes.
8.1 million people have diabetes, but have not been diagnosed.
28.9 million, or 12.3% of all people 20 years or older have diabetes.
208,000 people under 20 years old have diabetes.
11.2 million, or 25.9% of all people 65 or older have diabetes.
15.5 million, or 13.6% of all men aged 20 years or older have diabetes.
13.4 million, or 11.2% of all women aged 20 years or older have diabetes.
2012 - 1.7 million new cases of diabetes are diagnosed in people aged 20 years or older.
2012 - The CDC releases a report showing that 18 states had a 100% or more increase in the prevalence of diabetes from 1995 to 2010. Forty-two states saw an increase of at least 50%.