Diabetes mellitus is a group of diseases that involves high blood sugar (glucose) levels. Every cell in your body needs energy to function. When you eat, your body breaks down foods that have carbohydrates into glucose. While this happens, your pancreas releases a hormone called insulin.

Insulin acts as a “key.” It allows the glucose to go from the blood into the cells. It also helps you store energy. Insulin is a vital part of metabolism. Without it, your body isn’t able to function or perform properly.

Uncontrolled diabetes can lead to serious complications. It can cause damage to small and large blood vessels and organs. This can often lead to heart disease, stroke, kidney disease, nerve damage, and eye disease.

Managing diabetes requires keeping track of blood glucose levels. Treatment may include taking insulin or other medications. Healthy eating habits and regular exercise can also help manage diabetes.

Types of Diabetes

There are different types of diabetes. Each has something to do with insulin and blood glucose.

types of diabetes

Type 1 diabetes

Type 1 diabetes is a disorder in which the pancreas cannot longer produce insulin. It used to be called juvenile diabetes. It’s also sometimes called insulin-dependent diabetes mellitus. There is no cure. If you have it, you must take insulin to survive.

Type 2 diabetes

In type 2 diabetes, the pancreas can produce insulin, at least initially. But the body doesn’t respond to it or use it effectively. This is called insulin resistance. Over time, the ability of the pancreas to make insulin decreases. Then blood sugars go up.

Some, but not all people with type 2 diabetes need to take insulin. Most of the time a proper diet, exercise, and medications can manage the disease.

Gestational diabetes

Gestational diabetes develops during pregnancy. According to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), women with gestational diabetes have a 35 to 60 percent chance of developing type 2 diabetes within 20 years.


When blood glucose levels are higher than they should be, but not high enough to qualify as diabetes, you have prediabetes. This condition puts you at increased risk of type 2 diabetes. In many cases, changes in diet and exercise can delay or prevent onset of the disease.

Prevalence and incidence

diabetes prevalencediabetes prevalence

According to the Centers for Disease Control and Prevention (CDC), about 1 in 10 American adults has diabetes. If trends continue, that figure is expected to double or triple by 2050. In 2012, 13.4 million women (11.2 percent) had diabetes, according to the National Diabetes Report. About 15.5 million men (13.6 percent) had it.

According to the American Diabetes Association (ADA), there were 1.7 million new cases of diabetes in 2012. About 86 million Americans had prediabetes that year.

Type 2 diabetes represents about 90 to 95 percent of all diabetes cases. As many as three million Americans have type 1 diabetes, according to the Juvenile Diabetes Research Foundation (JDRF). About 15,000 children and 15,000 adults are diagnosed each year. Approximately 15 percent of Americans with type 1 diabetes are children. Among people under age 20, type 1 diabetes rose 23 percent between 2001 and 2009.

Gestational diabetes occurs in about 2 to 10 percent of all pregnancies.

Countries with the most adults living with diabetes in 2013*
China98.4 million
India65.1 million
United States24.4 million
Brazil11.9 million
Russian Federation10.9 million
Mexico8.7 million
Indonesia8.5 million
Germany7.6 million
Egypt7.5 million
Japan7.2 million

*Source: International Diabetes Federation (IDF)

Causes and risk factors

diabetes causes and risk factorsdiabetes causes and risk factors

Anyone can develop type 1 diabetes, but it’s usually diagnosed in childhood. Only about 5 percent of cases are diagnosed in adulthood. The exact cause is unknown. There is no cure or known prevention.

The risk of developing type 2 diabetes increases as you get older. You’re also more likely to get it if you’ve had gestational diabetes or prediabetes. Other risk factors include being overweight or having a family history of diabetes.

You can’t completely eliminate the risk of type 2 diabetes. A healthy diet, weight control, and regular exercise may help prevent it.

Certain ethnicities are at higher risk of developing type 2 diabetes. These include:

  • African-Americans
  • Hispanic/Latino Americans
  • Native Americans
  • Hawaiian/Pacific Island Americans
  • Asian-Americans


diabetes complicationsdiabetes complications

Diabetes is the seventh leading cause of death in the United States. Among adults 20 to 74 years old, diabetes is the top cause of blindness, according to the NIDDK. Diabetes is also a leading cause of kidney failure. Nervous system damage affects about 60 to 70 percent of people with diabetes, and can lead to a variety of nerve problems.

Many people with diabetes have impaired sensation in the hands and feet or carpal tunnel syndrome. Diabetes can also cause digestive problems and erectile dysfunction, and increases the risk of high blood pressure, heart disease, and stroke. Diabetes causes more than 60 percent of nontraumatic lower limb amputations.

Cost of diabetes

diabetes costdiabetes cost

According to the NIDDK, diabetes cost the United States $116 billion in direct medical costs in 2007. Indirect costs of disability, lost work, and early mortality are estimated at $58 billion. By 2012, direct medical costs rose to $245 billion. Indirect costs were $69 billion, according to the ADA. Healthcare for people with type 1 diabetes costs the United States about $14.9 billion each year, according to the JDRF. Also, healthcare costs are twice as high for people with diabetes then for those who don’t have it. Diabetes cost the world economy $376 billion in 2010. That’s about 11.6 percent of total world healthcare expenses. The IDF projects costs to rise above $490 billion by 2030.