The Definition

  • Diabetes mellitus refers to a group of diseases that affect how your body uses blood sugar (glucose).
  • Glucose is vital to your health because it’s an important source of energy for the cells that make up your muscles and tissues. 
  • It’s also your brain’s main source of fuel.
  • If you have diabetes, no matter what type, it means you have too much glucose in your blood, although the causes may differ. 
  • Too much glucose can lead to serious health problems.
  • Chronic diabetes conditions include type 1 diabetes and type 2 diabetes.
  • Potentially reversible diabetes conditions include prediabetes — when your blood sugar levels are higher than normal, but not high enough to be classified as diabetes — and gestational diabetes, which occurs during pregnancy but may resolve after the baby is delivered.
  • To understand diabetes, first you must understand how glucose is normally processed in the body.


How Insulin works:

  • Insulin is a hormone that comes from a gland situated behind and below the stomach (pancreas).
  • The pancreas secretes insulin into the bloodstream.
  • The insulin circulates, enabling sugar to enter your cells.
  • Insulin lowers the amount of sugar in your bloodstream.
  • As your blood sugar level drops, so does the secretion of insulin from your pancreas.


The Role of Glucose:

  • Glucose — a sugar — is a source of energy for the cells that make up muscles and other tissues.
  • Glucose comes from two major sources: food and your liver.
  • Sugar is absorbed into the bloodstream, where it enters cells with the help of insulin.
  • Your liver stores and makes glucose.
  • When your glucose levels are low, such as when you haven’t eaten in a while, the liver breaks down stored glycogen into glucose to keep your glucose level within a normal range.