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Diabetes Mellitus Overview

Updated: February 13, 2019

What Is It?

Diabetes mellitus is a condition defined by persistently high levels of sugar (glucose) in the blood. There are several types of diabetes. The two most common are called type 1 diabetes and type 2 diabetes.

During digestion, food is broken down into its basic components. Carbohydrates are broken down into simple sugars, primarily glucose. Glucose is a critically important source of energy for the body's cells. To provide energy to the cells, glucose needs to leave the bloodstream and get inside the cells.

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