How Insulin Works
| Author: Judy Kohn, RN, BSN, CDE |
| Last Updated: Friday, March 31, 2006 |
Q: "What does insulin do and why does the pancreas make extra insulin when a person eats?"
A: To answer that, we can look at how the body uses glucose, the 3 main roles of insulin and how people with diabetes take insulin.
How the body uses glucose:
- The cells in your body need glucose to function. You get glucose both from the food you eat and also from glucose that is stored in your liver.
- Every time you eat, the level of glucose in your blood rises; this stimulates the pancreas to release more insulin. Four to five hours after a meal, your blood glucose level returns to baseline. When you haven't eaten for a while and during the night when you are sleeping, your liver releases stored glucose to supply you with energy.
- Insulin is released in response to glucose in the blood.
How insulin works-it has 3 main roles:
- Regulates the liver from releasing too much glucose (I like to say that insulin leans up against the door of the liver and only lets a little glucose out at a time). When there is enough glucose in the blood, insulin tells the liver to shut down its production of glucose.
- Acts as a "doorman, or key" to open the doors of the cells (called receptors) and to allow glucose to enter the cells so the glucose can then be turned into energy.
- Acts as a "traffic cop", directing some of the glucose to be stored back into the liver and the muscles, and if you eat more than you need, the excess energy is stored as fat.
How people with diabetes take insulin:
- Some people with type 2 diabetes have insulin resistance, so they treat this with weight reduction, exercise, and medications specifically designed to target insulin resistance.
- Some people with type 2 diabetes make some insulin, but not enough so they take oral medication that stimulates the body to produce more insulin, and/or they take medication to delay the glucose from entering the small intestine.
- Some people with type 2 diabetes also inject insulin (either in combination with pills)-by taking 1-4 shots per day or via an insulin pump.
- All people with type 1 diabetes must inject insulin by syringe (2-4 shots per day) or with an insulin pump to mimic what their pancreas is unable to do-i.e. provide both background insulin (called the basal dose) to handle between meal times, as well as meal insulin (called bolus insulin) to handle the extra glucose rise after each meal.
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Related Links
Endocrine Web and the Norman Endocrine Surgery Clinic
http://www.endocrineweb.com
Important Notice: The responses provided by the team of Diabetes Educators are based on their personal experiences and expertise as practicing diabetes healthcare professionals, and are not to be considered diabetes management advice from Abbott Laboratories. Remember that information provided by the team of Diabetes Educators is for general background purposes and is not intended as a substitute for medical diagnosis or treatment by a trained professional. You should always consult your physician about any healthcare questions you may have, especially before trying a new medication, diet, fitness program, or approach to healthcare issues.
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