Diabetes: A Basic Introduction

Introduction to Diabetes

What is Diabetes?

It is a long term condition that affects the body’s ability to use glucose, which results in the body having high circulating blood glucose levels.

Terms for you to know, to better understand the condition:


Glucose:  An important energy source that is needed by the cells and organs of our bodies. Glucose or sugar comes from the food we eat. Carbohydrates such as fruit, bread pasta and cereals are common sources of glucose. These foods are broken down into sugar in our stomachs, and then absorbed into the bloodstream. The glucose is then transported to cells to provide them with energy. The cells cannot use glucose without the help of Insulin.

Diabetes develops when there is too much glucose in the blood. This can have serious health consequences. However, with careful management, people can continue to lead full, healthy and active lives.

Insulin: A hormone made by the pancreas that allows your body to use glucose from the food that you eat for energy or to store glucose for future use. Insulin helps keeps your blood sugar level from getting too high  or too low.

The cells in your body need glucose for energy. However, glucose cannot go into most of your cells directly. After you eat food and your blood sugar level rises, cells in your pancreas are signalled to release insulin into your bloodstream. Insulin then attaches to and signals cells to absorb sugar from the bloodstream. Insulin is often described as a “key,” which unlocks the cell to allow sugar to enter the cell and be used for energy.



Hyperglycaemia: High sugar levels in the blood

Hypoglycaemia: Low sugar levels in the blood

Pancreas: The Pancreas is a gland which lies behind the stomach. It manufactures and secretes enzymes and hormones. One of the hormones it secretes is Insulin.



Types of Diabetes

There are three different types: Type1, Type 2 and Gestational Diabetes

Type 1: Insulin-Dependent Diabetes
This is when the body can’t produce enough or any insulin.

Type 1 usually occurs before the age of 40 and accounts for only around 10% of all cases.
It is the most common childhood form of the condition and was previously called juvenile-onset diabetes.

Type 2: Non Insulin dependent diabetes

Type 2 is the most common form of the condition, accounting for 90 – 95% of cases. In type 2, the body does not respond properly to insulin, a condition known as insulin resistance. There are three stages in the progress of type 2 diabetes:

Stage One
The first stage in is when resistance to insulin develops. Normally insulin attaches to receptors on liver and muscle cells and facilitates the movement of blood sugar into the cells. In type 2 diabetes certain mechanisms prevent insulin from moving blood sugar into these cells. Most patients with type 2 produce variable, even normal or high, amounts of insulin. In the beginning, this amount is usually enough to overcome such resistance.

Stage Two
Over time, the pancreas becomes unable to produce enough insulin to overcome resistance. In type 2, the initial effect of this stage is usually an abnormal rise in blood sugar after a meal (called postprandial hyperglycaemia).

Stage Three
Eventually, the cycle of elevated glucose further damages beta cells, thereby drastically reducing insulin production and causing full-blown diabetes. This is made evident by fasting hyperglycaemia, in which glucose levels are high most of the time.

According to the American Cancer Society, Type 2 diabetes increases the risk of certain types of cancer. It is reported that diabetes doubles the risk for developing liver, pancreatic, or endometrial cancer. It is also believed that certain medications used for treating type 2 may possibly increase the risk for some types of cancers. Read more on Type 2 Diabetes.

Gestational Diabetes

Gestational diabetes is a form of type 2, usually temporary, that first appears during pregnancy. It usually develops during the third trimester of pregnancy. After delivery, blood sugar (glucose) levels generally return to normal, although some women develop type 2 within 15 years.

Because glucose crosses the placenta, a pregnant woman with diabetes can pass high levels of blood glucose to the foetus. This can cause excessive foetal weight gain, which can cause delivery complications as well as increased risk of breathing problems.

Children born to women who have gestational diabetes have an increased risk of developing obesity and type 2 of the condition. In addition to endangering the foetus, it can also cause serious health risks for the mother, such as preeclampsia, a condition that involves high blood pressure during pregnancy.



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