Diabetes mellitus is a term for a group of disorders that cause elevated blood sugar (glucose) levels in the body.

Glucose is a critical source of energy for your:

  • brain
  • muscles
  • tissues

When you eat, your body breaks down carbohydrates into glucose. This triggers the pancreas to release a hormone called insulin, which acts as a “key” that allows glucose to enter the cells from the blood.

If your body doesn’t produce enough insulin to effectively manage glucose, it can’t function or perform properly. This leads to symptoms of diabetes.

Diabetes that’s not well managed can cause serious complications by damaging blood vessels and organs. It can increase the risk of:

Nutrition and exercise can help manage diabetes, but it’s also important to track blood glucose levels. Treatment may include taking insulin or other medications.

Here’s a breakdown of the different types of diabetes:

  • Prediabetes: Blood glucose levels are higher than what’s considered normal, but they’re not high enough to qualify as diabetes.
  • Type 1 diabetes: The pancreas produces no insulin.
  • Type 2 diabetes: The pancreas doesn’t make enough insulin, or your body can’t use it effectively.
  • Gestational diabetes: People who are pregnant are unable to make and use all of the insulin they need.


According to the American Diabetes Association (ADA), people who develop non-insulin dependent diabetes mellitus (type 2 diabetes) nearly always have prediabetes. This means blood glucose levels are elevated, but they’re not yet high enough to be considered diabetes.

The Centers for Disease Control and Prevention (CDC) estimates 88 million adult Americans have prediabetes, and more than 84 percent go undiagnosed.

Type 1 diabetes

With type 1 diabetes, the pancreas can’t produce insulin. According to the ADA, almost 1.6 million Americans have this disorder.

Non-insulin dependent diabetes mellitus (type 2 diabetes)

Non-insulin dependent diabetes mellitus, or type 2 diabetes, is the most common form of diabetes.

With this disorder, the pancreas can initially produce insulin, but your body’s cells can’t respond to it effectively. This is known as insulin resistance.

The CDC notes that 90 to 95 percent of diagnosed cases are type 2 diabetes.

Gestational diabetes

Gestational diabetes develops during pregnancy. The CDC estimates between 2 and 10 percent of pregnancies in the United States are affected by gestational diabetes every year.

According to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), people with gestational diabetes will have a greater chance of developing type 2 diabetes within 10 years.

According to the CDC, more than 100 million adults in the United States are living with diabetes or prediabetes. And the ADA estimated in 2018 that of 34.2 million Americans with diabetes, 7.3 million didn’t know they had it.

The CDC reports there were 1.3 million new cases of diagnosed diabetes in 2017, suggesting new cases may be leveling off after rising for years.

Previously known as juvenile diabetes, type 1 diabetes is usually diagnosed in childhood. The CDC estimates less than 10 percent of people with diabetes have type 1.

While factors such as genetics and certain viruses may contribute to this disease, its exact cause is unknown. There’s currently no cure or any known prevention, but there are treatments to help manage symptoms.

Your risk for developing type 2 diabetes increases as you get older.

You’re also more likely to develop it if you’ve had gestational diabetes or prediabetes. Other risk factors include having obesity or overweight or having a family history of diabetes.

While 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, too, which is most likely due to inequities in the healthcare system.

The ethnic groups include:

  • African Americans
  • Hispanic/Latino Americans
  • Native Americans
  • Pacific Islanders
  • Asian Americans

Blindness is a common diabetes complication.

Diabetic retinopathy, in particular, is the most common cause of blindness among people with diabetes. It’s a leading cause of vision loss among working-age adults, according to the National Eye Institute.

Diabetes is also a leading cause of kidney failure. Nervous system damage, or neuropathy, also affects up to half of people with diabetes.

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.

The condition increases the risk of heart disease and stroke, and it’s associated with an increased risk of high blood pressure.

Diabetes can also lead to amputation of the lower limb.

According to the ADA, diabetes is the seventh leading cause of death in the United States.

The ADA estimates in 2017 that diagnosed diabetes led to some $237 million in direct medical costs such as inpatient care and prescription medication, as well as another $90 million in reduced productivity.

If you or a loved one is living with diabetes, it’s important to keep it well-managed. Eating well, staying active, following all directives from your healthcare team, and keeping up with medical appointments is a great way to do that.

If you are experiencing any symptoms of diabetes, especially if you have any risk factors, reach out to your healthcare provider for guidance and testing.