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How insulin works

How insulin works image

Insulin acts like a key, opening body cells so that glucose can enter the cell to provide a source of energy.

Insulin is like the key to a car. A car needs fuel to run, but the key provides the spark that releases the fuel.

In your body, insulin is used to "spark" the use of glucose as fuel in your cells.


Normal body cell

Cell doors are open to allow insulin to bring glucose into the cells to use for energy.

Normal body cell image  

Insulin resistant body cell

Cell doors are shut. The glucose cannot get into the body cells so they stay in the bloodstream.

insulin resistant body cell image


Source: Allina Patient Education, Prediabetes: Reducing Type 2 Diabetes Risk Through a Lifestyle of Good Nutrition and Activity, first edition, dia-ahc-94403

First published: 04/02/2009
Last updated: 04/02/2009

Reviewed by: Allina Patient Education experts