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Glucose is your body's main source of energy. It's a type of sugar.

• Glucose comes from food. The main source of glucose is carbohydrates. You get carbohydrates from rice, pasta, potatoes and other starchy foods. Sugar is also a type of carbohydrate.
• You can also get glucose from some fruits and vegetables.
• When you eat these foods, your digestive system breaks them down into a form that your body can use.
• Broken down food products travel to your liver. Your liver turns them into glucose. Your liver can also make glucose from scratch.

Glucose goes into your bloodstream from your liver. The glucose can then be carried around your body, supplying all your cells with this vital fuel.

For more information, see How does my body control my blood glucose level?

This information is for educational use only, and is not a substitute for prompt professional medical advice. Readers should always consult a physician or other professional for advice and treatment. ©BMJ Publishing Group Limited 2008. All rights reserved.