Health Topics

Diabetes – Understanding Metabolism


To better understand diabetes, it helps to know more about how the body uses food for energy (a process called metabolism). Your body is made up of millions of cells. To make energy, the cells need food in a very simple form. When you eat or drink, much of your food is broken down into a simple sugar called glucose. Glucose provides the energy your body needs for daily activities.

The blood vessels and blood are the highways that transport sugar from where it is either taken in (the stomach) or manufactured (in the liver) to the cells where it is used (muscles) or where it is stored (fat). Sugar cannot go into the cells by itself. The pancreas releases insulin into the blood, which serves as the helper, or the "key," that lets sugar into the cells for use as energy.

When sugar leaves the bloodstream and enters the cells, the blood sugar level is lowered. Without insulin, or the "key," sugar cannot get into the body's cells for use as energy. This causes sugar to rise. Too much sugar in the blood is called "hyperglycemia" (high blood sugar) or diabetes.

What Is Insulin?

Insulin is a naturally occurring hormone, produced by the beta cells of the pancreas, which helps the body use glucose for energy.

What Are the Symptoms of Low Blood Sugar?

Most people have symptoms of low blood sugar (hypoglycemia) when their blood sugar is less than 60 mg/dl. (Your healthcare provider will tell you how to test your blood sugar level.)

When your blood sugar is low, your body gives out signs that you need food. Different people have different symptoms. You will learn to know your symptoms.

Common low blood sugar symptoms include the following:

Early symptoms

You may:

  • Feel weak
  • Feel dizzy
  • Feel hungry
  • Tremble
  • Feel shaky
  • Sweat
  • Have a pounding heart
  • Have pale skin
  • Feel frightened or anxious

Late symptoms

You may:

  • Feel confused
  • Have a headache
  • Feel cranky
  • Have poor coordination
  • Have bad dreams or nightmares
  • Be unable keep your mind on one subject
  • Feel a numbness in your mouth and tongue
  • Pass out