Type 2 diabetes (formerly called ‘adult-onset’ or ‘non insulin-dependent’) is a chronic condition in which the body doesn’t produce enough insulin and/or is unable to use insulin properly. Instead of converting sugar into energy, it backs up in the bloodstream and causes a variety of symptoms.

Type 2 diabetes usually occurs in people who are over 40 years of age, overweight and have a family history of diabetes, although today it is increasingly found in younger people. Type 2 diabetes is the most common form of diabetes. It’s caused by a combination of factors but usually begins with insulin resistance. Insulin comes from the pancreas and acts as a key to let blood glucose into the cells where it is converted to energy.

In normal body function, the pancreas produces enough insulin to handle the blood glucose generated by the food you eat. When someone has insulin resistance, however, the cells do not respond to the insulin as well and blood glucose cannot enter the cells as easily to produce energy. Because of this, excess glucose builds up in the bloodstream.

In the early stages of the disease, the pancreas responds by making more insulin than normal in an attempt to overcome insulin resistance. Eventually, the body cannot produce enough insulin to overcome this resistance and that is when type 2 diabetes develops.

The longer you have diabetes, the more difficult it is for your body to overcome this insulin resistance.

The secret to keeping the beta cells in your pancreas producing insulin normally for a long time is to reduce insulin resistance with lifestyle interventions, such as weight loss, healthy eating, and regular physical activity, and by keeping your blood glucose levels as close to normal as possible.

While type 2 diabetes may often be managed with lifestyle interventions or oral medications, insulin is sometimes required.

What causes type 2 diabetes?

Type 2 diabetes can be caused by a variety of factors: being overweight, being physically inactive, or your body’s inability to properly use the insulin it produces. In addition, those who have been previously identified as having impaired fasting glucose (IFG) or impaired glucose tolerance (IGT) are also at risk.

What are the symptoms of type 2 diabetes?

People with type 2 diabetes frequently experience certain symptoms. These include:

  • being very thirsty
  • frequent urination
  • blurry vision
  • irritability
  • tingling or numbness in the hands or feet
  • frequent skin, bladder or gum infections
  • wounds that don't heal
  • extreme unexplained fatigue

In some cases of type 2 diabetes, there are no symptoms. In this case, people can live for months, even years, without knowing they have the disease. This form of diabetes comes on so gradually that symptoms may not even be recognized.

Who gets type 2 diabetes?

Risk factors for type 2 diabetes include obesity, high cholesterol, high blood pressure, and physical inactivity. The risk of developing type 2 diabetes also increases as people grow older

Having any of the following factors also puts you at a higher risk of developing type 2 diabetes:

  • You are African American, Hispanic American, Asian American, Native American or Pacific Islander
  • You have a parent or sibling with type 2 diabetes
  • You are generally physically inactive
  • You’ve already been told you have pre-diabetes
  • You had gestational diabetes or a baby who weighed more than nine pounds
  • Your blood pressure is 140/90 or above
  • Your triglyceride level is above 250 mg/dl or your HDL is below 35 mg/dl

The more risk factors you have, the higher your chance of developing type 2 diabetes. If you have any of the above risk factors, ask your health care provider to test you for diabetes.

Can diabetes be cured?

Currently, there is no cure for type 2 diabetes. There has been speculation about the role of gastric bypass surgery in "curing" type 2, however, a causal link has not been established between the surgery and the cure of type 2 diabetes.

How is type 2 diabetes treated?

Type 2 diabetes is often treated with oral medication because many people with this type of diabetes make some insulin on their own. The pills people take to control type 2 diabetes do not contain insulin. Instead, medications such as metformin, sulfonylureas, alpha-glucosidase inhibitors, and many others are used to make the insulin that the body still produces more effective.

Some people with type 2 diabetes are treated with insulin. Insulin is either injected with a syringe several times per day or delivered via an insulin pump. The goal of insulin therapy is to mimic the way the pancreas would produce and distribute its own insulin if it were able to manufacture it. Taking insulin does not mean you have done a bad job of trying to control your blood glucose—instead, it simply means that your body doesn’t produce or use enough of it on its own to cover the foods you eat.

One of the key factors in Joslin’s treatment of diabetes is tight blood glucose control, so be certain that your treatment helps get your blood glucose readings as close to normal as safely possible. Patients should discuss with their doctors what their target blood glucose range is. It is also important to determine what your goal is for A1C readings (a test that determines how well your diabetes is controlled over the past 2-3 months). By maintaining blood glucose in the desired range, you’ll likely avoid many of the complications some people with diabetes face.

What kind of complications are people with diabetes susceptible to?

Blood travels throughout your body, and when too much glucose (sugar) is present, it disrupts the normal environment that the organ systems of your body function within. In turn, your body starts to exhibit signs that things are not working properly inside—those are the symptoms of diabetes people sometimes experience. If this problem—caused by a variety of factors—is left untreated, it can lead to a number of damaging complications such as heart attacks, strokes, blindness, kidney failure, and blood vessel disease that may require an amputation, nerve damage, and impotence in men.

The good news is that prevention plays an important role in warding off these complications. By maintaining tight control of your blood glucose—and getting it as close to normal as possible—you’ll help your body function in the way that it would if you did not have diabetes. Tight control helps you decrease the chances that your body will experience complications from elevated glucose levels.

Can diabetes be prevented?

Research has shown that there are some ways of preventing type 2 diabetes or at least delaying its onset. Lifestyle changes such as becoming more active (or staying active, if you already engage in regular physical activity) and making sure your weight stays in a healthy range are two ways to help ward off type 2 diabetes but talk to your doctor about what else you can do to prevent or manage the disease.

Although this content is reviewed by Joslin Diabetes Center healthcare professionals it is not intended to replace the medical advice of your doctor or healthcare provider. Please consult your healthcare provider for advice about a specific medical condition

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