Type 2 Diabetes: Test Your Medical IQ

Adult-onset diabetes is another term for type 2 diabetes, or diabetes mellitus. Type 2 diabetes is often referred to as adult-onset diabetes because it is often diagnosed in adults, though children and teens may also develop the disease. Type 2 diabetes is a chronic condition characterized by high blood sugar (glucose) levels caused by the body's inability to use insulin properly.

The hormone that helps the body use sugar (glucose) for energy is called insulin. Insulin is made by the body in the pancreas and when the body cannot produce enough insulin on its own, it needs to be taken by injection or other means.

Everyone who has type 1 diabetes (previously known as juvenile diabetes) must take some form of insulin therapy. Some people with type 2 diabetes will also need insulin supplementation. There are different types of insulin available, and they differ in chemical structure and how long they last in the body.

The organ in the body that makes insulin is the pancreas. This hand-sized organ is located behind the lower part of the stomach. It produces enzymes to help digest food in the intestine and makes hormones including insulin, which is important in regulating blood sugar levels.

There are differences between type 1 diabetes and type 2 diabetes. Type 1 diabetes used to be called juvenile diabetes because it tends to develop in childhood as a result of a damaged pancreas that produces little to no insulin. In contrast, type 2 diabetes used to be called adult-onset diabetes because it tends to be diagnosed later in life. In type 2 diabetes, the body has increasing difficulty absorbing and using the insulin produced by the pancreas.

Type 2 diabetes makes up about 90% of cases of all diabetes, making it far more common than type 1 diabetes.

Diabetes is the 7th leading cause of death in the United States as of 2013, with 75,578 death certificates listing it as the underlying cause of death, according to the Centers for Disease Control (CDC).

The best predictor – or most major risk factor – for type 2 diabetes is being overweight or obese. Nearly 90% of people with type 2 diabetes are overweight or obese, and this puts additional pressure on their body's ability to use insulin to efficiently control blood sugar (glucose) levels. The number of cases of diabetes among American adults grew by one-third in the 1990s and because obesity is on the rise in the U.S., the number of diabetes cases among American adults is expected to continue to increase.

Other risk factors for type 2 diabetes include age, race, pregnancy, stress, certain medications, genetics or family history, and high cholesterol.

In general, type 2 diabetes is preventable. Just a 5-10% weight loss along with lifestyle changes such as exercise may prevent or delay the development of type 2 diabetes in at-risk individuals. Studies have shown that diet and moderate physical activity (such as walking a total of 150 minutes per week – about 30 minutes per day, 5 days a week) can reduce weight and reduce the development of diabetes by 40-60%.

The best way to prevent type 2 diabetes is to maintain a healthy weight, to increase activity, and to lose weight if you are overweight.

It's a myth that simply eating too much sugar causes diabetes. Type 1 diabetes is genetic, and it is unknown what triggers the disease, while type 2 diabetes is a combination of genetics and lifestyle.

Where sugar enters the equation is that being overweight is a risk factor for developing type 2 diabetes, and a diet high in calories and sugar can contribute to weight gain. Research has shown that drinking sugary drinks is linked to developing type 2 diabetes.

The American Diabetes Association recommends avoiding sugar-sweetened beverages including regular soda, fruit punch, fruit drinks, energy drinks, sports drinks, sweet tea, and other sugary drinks, to help prevent diabetes. Sugary drinks such as these raise blood sugar (glucose) and can contain several hundred calories per serving!

Symptoms of type 2 diabetes are related to high blood sugar levels (hyperglycemia). Symptoms may not be present at first because type 2 diabetes can develop gradually over time. High blood sugar levels can result in symptoms including thirst, frequent urination, tiredness, listlessness, nausea, and dizziness. If the blood sugar levels are extremely high, symptoms may escalate to confusion, drowsiness, and even loss of consciousness (diabetic coma, which is a medical emergency).