Types of Diabetes

The key to understanding diabetes is having a good idea of how the body works and what changes when you have diabetes. Once you know how diabetes "works" in its various types, it's easier to see how complications can arise, and why insulin therapy and blood glucose monitoring are important. 
We'll start by learning how our bodies convert the food we eat into the energy we need to live. During digestion, our bodies break down food into three basic groups: 

  • Proteins (found in meat, fish, eggs, and other dairy products)

  • Fats (found in vegetable oils, meat, cheese, and other dairy products)

  • Carbohydrates (also known as starches or sugars; found in bread, pasta, fruits, and vegetables)  

Carbohydrates are broken down into glucose (also known as "blood sugar"), which is the "fuel" that gives our bodies energy. For blood sugar to get into the body's cells, the help of a hormone called "insulin" is required.

Diabetes is caused by a problem with the body's ability to use insulin. 

  • In type 1 diabetes, the body produces little or no insulin.

  • In type 2 diabetes, gestational diabetes, and the other types of diabetes, the body does not produce enough insulin or cannot use the insulin it produces (this is called "insulin resistance").

If insulin isn't being used properly, then blood sugar can't get into the cells and it backs up in the bloodstream. The body tries to get rid of the excess sugar through the urine.

  • People with type 1 diabetes are at risk for developing diabetic ketoacidosis if not treated.

  • In type 2 and other cases, untreated high blood sugar will, over time, affect your health by causing diabetes complications. In fact, a number of type 2 patients already have complications at the time they are diagnosed with diabetes.


The BD Diabetes Learning Center describes the causes of diabetes, its symptoms, and diabetes complications such as retinopathy and neuropathy. This site contains detailed information about blood glucose monitoring, insulin injection and safe sharps disposal. Interactive quizzes, educational literature downloads and animated demonstrations help to teach diabetes care skills.

Important Note: The content of this website is not intended to be a substitute for professional medical advice, diagnosis or treatment. Do not disregard your doctor's advice or delay in seeking it because of something you have read in this website.

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