Introduction to Diabetes Mellitus
Diabetes Mellitus (DM) is the term used to describe a group of similar disorders where affected individuals have too much glucose, or sugar, in their blood.
The medical term for this is hyperglycemia. Diabetes Mellitus is often shortened to just diabetes, however this regularly causes a lot of confusion as there are many different types and causes of the disease.
When doctors use the term “diabetes”, they are often referring to type-2 diabetes, as it is by far the most common.
The subtypes of Diabetes Mellitus
The subtypes of Diabetes Mellitus include:
- Type 1 DM
an autoimmune disease which destroys the cells which make insulin.
- Type 2 DM
associated with obesity, lack of exercise and eating too much sugary food.
the initial stages, or symptoms, leading up to the onset of full blown type 2 diabetes.
- Gestational DM
a condition which affects up to 10% of pregnant women.
In addition to the main types mentioned above, other types of diabetes can be caused by certain drugs such as steroids, and diseases such as cystic fibrosis.
There is also a type of diabetes known as Diabetes Insipidus, which has nothing to do with blood sugar or insulin and so is probably of little interest to you.
Before we begin discussing the types of diabetes, it would be useful for you to first have a basic understanding of of how glucose is regulated by your body, and the role that insulin plays in achieving this.
How Your Body Regulates Blood Glucose
All of the subtypes of diabetes are caused by problems with an extremely important hormone called insulin, whose sole job it is to keep your blood glucose levels down.
But what actually is glucose?
Glucose is basically another name for sugar, and it is one of the main sources of energy for all of the cells in your body. It comes from carbohydrate in the food that you eat and is stored in your liver in an inactive form called glycogen.
When your glucose levels are low, such as after a period of fasting, the liver releases some of its glucose stores. It then enters the blood to be distributed around your body.
However, glucose is unable to get into your cells to provide them with energy without the help of insulin.
Imagine that the cell wall is dotted with hundreds of tiny doorways, called glucose transporters. These are tiny proteins which act as a “tunnel” to allow glucose to enter the cell. However, these doorways are locked most of the time.
Insulin acts as the key to open these minute doorways allowing glucose to enter.
Insulin is produced by the pancreas, which is found just below the stomach. After you eat a meal and glucose starts to be absorbed, the pancreas detects it and begins to secrete insulin into the blood.
The insulin circulates around the body and begins to unlock those little doorways. This allows the glucose to exit the blood and enter the cells.
Therefore, the overall effect of insulin is to lower blood glucose. Once insulin has done its job and most of the glucose has moved into your cells, the pancreas detects this and stops producing insulin.
In the Diabetic Patient…
People with diabetes are unable to keep their blood glucose levels down becuase of a problem with their insulin.
Either your body is not producing enough insulin to cope with the amount of sugar in your blood
(such as in type 1 diabetes), or else the insulin that is being produced is not as effective as it is supposed to be
Both of these problems cause glucose to build up in the blood.If glucose levels reach a critical point, a condition known as diabetic ketoacidosis (DKA) can occur. This is a medical emergency and patients need immediate help by a medical professional. DKA usually only occurs in type 1 diabetics who have no insulin at all. It is very unusal in a type 2 diabetic, as they usually have some working insulin which prevents it from occuring.
DKA is discussed further in the type 1 diabetes category.
If blood glucose remains elevated over a period of years this can cause serious damage to blood vessels, resulting in subsequent damage to organs with delicate vessels, such as the kidneys and the eye.