Diabetes has reached virtually epidemic levels in the modern world. In 2005 the U.S. Centers for Disease Control and Prevention estimated that about 7 percent of the American population (20.9 million people) had diabetes--and 6.2 million of them were unaware of it. More than 1.5 million people over the age of 20 will be diagnosed with it in the U.S. this year. About 21 percent of those older than 60 have the disease.
Small wonder, then, given the severe complications associated with diabetes, that it continues to be the sixth leading cause of death in the U.S. And although diabetes was often called a disease of affluence in the past, it is now one of the fastest-rising health concerns in developing nations as well: the World Health Organization pegs the global total at more than 171 million cases.
An unfortunate catch-22 of diabetes is that although the right diet and exercise can help with its prevention and management, diabetes itself can complicate both eating and physical activity. Patients may need to pay extra attention to taking meals on a regular schedule and to monitoring how exercise dehydrates them or lowers their blood glucose. Some may fail to comply consistently with prescribed regimens that seem inconvenient or unpleasant, thereby raising their risk of complications. But thanks to leaps in science's understanding of the disease, doctors now wield a diverse and growing arsenal of drugs and management technologies to fight the progression--and even onset--of illness. People with diabetes have more and better options than ever before for enjoying healthy, active, long lives.
Diabetes is a disease in which too much of a sugar called glucose accumulates in the blood because of a breakdown in how the body makes or reacts to the hormone insulin. Insulin enables muscle, fat and other types of cells to take up and process glucose. If cells can't burn or store glucose normally and the blood levels rise chronically, damage accumulates throughout the body--in the worst cases leading to blindness, amputation, kidney failure or death.
Most cases fall into one of two categories:
Type 2 diabetes, which has become increasingly prevalent during the past few decades, arises from insulin resistance, which causes cells, for poorly understood reasons, to stop responding properly to the hormone. At first, the pancreas can compensate by producing greater amounts of insulin. But over time, the pancreas reduces its production, making matters worse. Initially this type of diabetes may respond to diet, exercise and weight control, but later medications, and perhaps insulin, may be necessary depending on the severity of the case.
In addition, about 4 percent of all pregnant women develop gestational diabetes, a form that usually resolves itself after delivery. Diabetes can also be a rare consequence of certain genetic conditions or chemical exposures.
Symptoms, Risk Factors and Diagnosis
More than six million Americans have type 2 diabetes and don't know it because its early symptoms can seem so harmless and vague:
- Frequent urination
- Extreme thirst and hunger
- Blurred vision
In contrast, type 1 diabetes comes on more quickly and with more prominent symptoms, such as unexplained rapid weight loss, dehydration or a severe illness called ketoacidosis. Medical science has still not yet determined precisely why some people develop diabetes and others do not--the genetic and environmental triggers for the disease are surprisingly complex.