What is insulin and why does it need to be injected?

Ask our CDE

What is insulin and why does it need to be injected?

Dear Diabetes Educator,

My name is Lori and my doctor told me I have diabetes and need to take insulin. I don’t understand what insulin is and why I need to use a needle to inject it. I would like to take an insulin pill instead. Please explain this to me.

Dear Lori,

Thank you for your question. Insulin is a hormone made in the beta cells of the islets of Langerhans which is located in the pancreas. When you eat, the fats proteins and carbohydrates in our food is broken down to be used by our body.  These substances are called macronutrients and are needed for growth and maintenance.

The carbohydrates in our food are broken down to glucose as part of the digestion process.  Glucose travels through the bloodstream to the cells in our body to be used as energy.  To enter most cells, insulin is needed.  Without insulin, glucose builds up in the bloodstream.

When the body cannot make insulin or make enough insulin, it must be taken through injection. Pills that are used to help control diabetes are not insulin. These pills are to help the body use the insulin it already makes.

The hormone insulin is made up of proteins that if taken by mouth is denatured by the digestive process. This   would inactivate the insulin.  Therefore, when the body can’t make insulin, it can’t be taken in pill form and at this time must be injected. 

*Please ask your physician and medical team for guidance in understanding the types of insulin you need and when and how much to take. You should also learn how to properly inject your insulin.  Ask your doctor if you can see a diabetes educator to learn all about insulin and other aspects of taking care of your diabetes.