What does insulin do in my body?

Insulin enables glucose to enter the cells in your body. Glucose is a fuel that your body uses for energy. Glucose travels around in your bloodstream so it can reach all the cells in your body. Your body is made up of millions of cells, and they all need glucose so they have enough energy to do their jobs and keep you healthy. However, the cells are locked, and the only way for glucose to get in is if insulin lets them in. Insulin is the key to the locked cells.

One of insulin’s most important jobs is to help cells use glucose.

Insulin acts like a key to unlock the door that lets glucose into the cell. Cells in the body use glucose as a source of energy that they need to live. Without energy, the cells in the body cannot survive. Insulin also helps the body to store extra fuel as fat.

Insulin is a hormone made by the pancreas that helps the body store and use glucose.

Think of insulin as the U.S. Postal Service and glucose as the mail; insulin is responsible for delivering that glucose (sugar) from the bloodstream into muscle, fat, liver, and most other cells so that your body can use it for fuel.

I wish insulin had a similar mantra to the USPS-neither blood, not fat, nor DNA will keep insulin from delivering glucose throughout the body-but doesn't quite work that way. And problems happen either when the pancreas doesn't make enough insulin or because various parts of the body block insulin and prevent it from delivering glucose to those cells.

Dr. Mehmet Oz, MD
Cardiologist (Heart Specialist)
Insulin controls the amount of sugar from digested foods circulating in your bloodstream, and allows cells to use the sugar for fuel or be stored for future needs. Watch the animation to learn the basics about insulin.
Kate Myerson
Nutrition & Dietetics Specialist
I like to think of insulin as being the key to a car. The car is our body and instead of gas we run on glucose. The gas gauge is like a blood glucose meter, we can run without it for a while but it is really useful for telling us when we are going to run out of energy. Without the key to the car (insulin) we are not going anywhere. We need insulin to use the sugar to give us energy. 

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.