What is Diabetes?  

Diabetes is a condition in which the body cannot properly process sugar, glucose, for use as energy. In turn, blood sugar levels remain high, leading to health complications.

Key Takeaways

  • The two main types of diabetes are type 1 and type 2.

  • In type 1 diabetes (juvenile-onset or insulin-dependent diabetes), the body does not make any insulin. In type 2 diabetes (adult-onset or non-insulin-dependent diabetes) the body produces insulin, but the cells don’t respond to insulin the way they should.

  • A1C tests measure average blood glucose over the past two to three months.

  • Gestational diabetes, usually diagnosed during mid- to late-pregnancy, is when the mother’s body cannot overcome insulin resistance, thereby increasing blood sugars. 

What is Diabetes

Key Players

Blood sugar, or glucose, is the body’s primary source of energy. Glucose comes from nutrients in food like carbohydrates, fat and proteins. Normally, carbs are all broken down into glucose, which leaves the intestine, travels through the liver and enters the bloodstream. Its final destination is the body’s cells, where it is used to create energy. Insulin, a hormone produced by the beta cells of the pancreas, allows glucose to enter cells. 

How does the body maintain the status quo?

In the pancreas, beta cells sense an excess of glucose in the blood, such as just after a meal, and release insulin into the bloodstream. Blood glucose levels are maintained in a normal range after a meal through this interaction between glucose, beta cells and insulin.

In both types of diabetes, this balance between glucose and insulin is interrupted and the body is unable to use and store glucose properly. As a result, glucose builds up in the bloodstream. If left untreated, high blood sugar levels can cause damage to various parts of the body over time.  

Type 1 Diabetes

What is it?

Type 1 diabetes is also called insulin-dependent diabetes or juvenile-onset diabetes because it often begins in childhood. However, type 1 diabetes can occur at any age. It is an autoimmune disease in which the body can’t produce insulin. Remember, the body needs insulin to get sugar into the body’s cells to make energy. 

What causes it?

The body’s immune system attacks and destroys its own insulin-producing cells in the pancreas called beta cells. As a result, there is an insufficient number of beta cells to secrete insulin throughout the body when blood sugar is high.  Less insulin means that glucose is locked out of cells, and stays in the bloodstream where it continues to build up. 

How is it treated?

Since the body completely stops making insulin, patients must take daily insulin injections. Most people with type 1 diabetes need to start injecting insulin as soon as they are diagnosed. Type 1 cannot be controlled solely with diet, unlike type 2 diabetes. The necessity for treatment with insulin is why type 1 is classified as insulin-dependent.  

Type 2 Diabetes

What is it?

Type 2 diabetes is also called adult-onset or non-insulin-dependent diabetes. In this form of diabetes the body produces insulin, but the cells don’t respond to insulin the way they should (insulin resistance). 

What causes it?

In type 2, the body still produces insulin, but the body’s cells don’t respond to it effectively. In response to insulin resistance, a healthy pancreas typically makes more and more insulin to compensate. However, the pancreas doesn’t respond this way in patients with type 2 diabetes. Because of these two problems, insulin resistance and trouble making extra insulin, insulin cannot effectively move the glucose from the blood into the cells. So, glucose accumulates in the bloodstream much like in type 1 leading to long-term health complications if left untreated. 

Type 2 diabetes is more likely to occur in people who are over the age of 40, overweight and have a family history of type 2 diabetes, although an increasing number of younger people, including adolescents, are developing type 2 diabetes.

How is it treated?

One can prevent type 2 diabetes through maintaining a moderate weight, exercise and diet. Treatment for type 2 diabetes involves keeping a healthy weight, eating right and exercising. Some people need medication, too.

How are T1 and T2 diagnosed?

The primary test used to diagnose both type 1 and type 2 diabetes is known as the A1C, or glycated hemoglobin, test. Symptoms of both types of diabetes consist of: urinating frequently and feeling very thirsty, hungry or fatigued. 

Although many of the symptoms of type 1 and type 2 diabetes are similar, they present in very different ways. The symptoms of type 1 diabetes develop quickly, typically over the course of several weeks. On the other hand, most people with type 2 diabetes won’t have symptoms for many years. Their symptoms often develop slowly over the course of time, with some people never developing any symptoms at all until complications arise. 

Gestational Diabetes 

Gestational diabetes occurs when one’s body can’t make enough insulin during their pregnancy to overcome insulin resistance. During pregnancy, the mother’s body makes several hormones that make cells resistant to insulin. While it sounds strange that the body would do this, there is a reason.

Insulin resistance allows sugar from the food the mom eats to go directly to the fetus for energy instead of the mother. This hormonal change is normal and mothers are typically able to increase their insulin production to overcome this resistance. However, in mothers with gestational diabetes, the pancreas doesn’t produce enough insulin to overcome the resistance, leading to high blood sugars. 

Gestational diabetes usually develops around the 24th week of pregnancy, so women are typically tested for it between 24 and 28 weeks. Approximately three to eight percent of all pregnant women in the United States are diagnosed with gestational diabetes. 

Gestational diabetes pose potential risks for the baby, such as unusual weight gain before birth, trouble breathing at birth and a higher risk of obesity and diabetes later in life. Gestational diabetes can be treated with daily exercise, weight maintenance, diet control and, if needed, insulin to control blood sugar.   


Outside the Huddle


Reviewed by Geetika Rao, MPH | Edited and Fact checked by Jared Dashevsky, M.Eng.