Diabetes: what you should know to better understand this condition

Sinéad Powell

Senior Dietitian, Regional Development Officer, Diabetes Ireland

Diabetes mellitus is a lifelong condition that can be diagnosed at any age and is caused by an absence or insufficiency of insulin. 

Insulin is a hormone made by the pancreas. It regulates the level of glucose (sugar) in the body. With diabetes, the pancreas makes too little insulin (or none) to enable all the glucose in your blood to get into your muscle and other cells to produce energy. If glucose can’t get into the cells to be used, it builds up in the bloodstream. Therefore, diabetes is characterised by high blood sugar (glucose) levels. 

 Types of diabetes 

There are many types of diabetes, but the three main types are:  

• Type 1 diabetes: always requires treatment with insulin injections or via an insulin pump. It is known as an autoimmune condition where the body’s immune system destroys the insulin-making cells (beta-cells) of the pancreas. It can occur at any age.  
• Type 2 diabetes: usually develops slowly in adulthood. It is progressive and can sometimes be treated with diet and exercise; but more often, type 2 diabetes may require medications and/or insulin injections. 

• Gestational diabetes: occurs during pregnancy but usually disappears when the baby is born. Women diagnosed with gestational diabetes are at a higher risk of developing diabetes at a later stage. 

Diabetes is characterised by high blood sugar (glucose) levels.

Main differences: type 1 and type 2 

The main difference between both types is in causes and treatments. In type 1 diabetes, insulin is not produced, and insulin therapy is required from the start. In type 2, insulin is produced but the body does not use it properly, so the treatment focuses on managing glucose levels through lifestyle and/or medications.  

Prevalence in Ireland 

We do not have a diabetes register in Ireland, but it is estimated that up to 300,000 people live with diabetes in Ireland — of those, approximately 261,300 live with type 2. Type 2 is the most prevalent chronic condition in people between 45–75 years old; and according to a recent 2021 Healthy Ireland survey, it is expected that the number of people with type 2 diabetes will increase by 60% over the next 10–15 years.