4 mins

What is diabetes?

This article explains the most common types of diabetes and how they arise, as well as some risk factors and signs and symptoms to look out for.

12 December 2022
Lady smiling whilst reading from a laptop screen

“What is diabetes?” might have been the first question you had when you were diagnosed, and it might be the first question a family member or friend asks.

Diabetes is when the body does not make enough insulin or is unable to use the insulin it produces, resulting in too much glucose (sugar) in the blood.

What causes diabetes?

What causes diabetes is different for every individual - there is no one cause. Everyone has different lifestyles, habits and genetic factors that could contribute to the condition. There are risk factors that can increase the chances of someone developing diabetes, yet having these factors does not mean diabetes is certain. Knowing the risk factors and early warning signs can help you take preventative action.

Risk factors Signs & symptoms
Weight gain Cold sweat
Infections Fatigue and tiredness
Pregnancy Palpitations
Surgeries Frequent urination and in large quantities
Aging Slow healing
Heavy thirst
Extreme hunger

What are the different types of diabetes?

Type 1 diabetes

Type 1 diabetes is present in around 8%1 of people with diabetes and is usually diagnosed in children and adolescents. It is believed to be caused by the body’s immune cells attacking and destroying (by mistake) the insulin-producing beta cells in the pancreas, which means they can no longer produce insulin2.

Treatment for type 1 diabetes requires the use of insulin.

Type 2 diabetes

Type 2 diabetes accounts for around 90%1 of all people with diabetes. In people living with type 2 diabetes, their bodies either cannot make enough insulin or are unable to use it properly2. Type 2 diabetes is mainly diagnosed in adults. Because it often presents with few symptoms, it can progress for many years without being diagnosed.

Type 2 diabetes can be associated with obesity and a sedentary lifestyle but it is important to remember that this isn’t always the case. In most cases, it is treated with diet and lifestyle changes. Tablets are also used for treatment, but in some cases insulin may be required.

Find out more about type 1 diabetes by watching our Introduction to diabetes video.

Gestational diabetes

For some women, when they are pregnant, gestational diabetes can occur. This is where hormone changes cause high levels of blood glucose, and the body is not able to produce enough insulin to enable cells to absorb and use it2. Most of the time, this type of diabetes goes away after the baby is born. However, it does put you at a higher risk of developing type 2 diabetes later in life.

Remember, diabetes is not your fault or something to blame yourself for. You are facing an unexpected change - but one you have the opportunity to manage. Managing your diabetes may require lifestyle changes. In some cases, it might also include medication and/or insulin.

What happens after a diabetes diagnosis?

Depending on the type of diabetes you have, you might be advised around diet and lifestyle changes. Treatments for diabetes can vary from tablets to insulin, depending on the person.

Your healthcare professional will probably introduce you to checking your blood sugar. Most people check their blood sugar by pricking a finger to apply a small drop of blood to a test strip. The test strip is then inserted into a measuring device called a blood glucose meter.

What does insulin do?

Insulin is a hormone produced by the pancreas that allows the glucose in our blood to enter our cells and be used to provide energy. When carbohydrates in food are digested and broken down into glucose, this enters the bloodstream. Insulin then enables the glucose to move into cells, where it is broken down for energy.

When a person has diabetes, their body still breaks down the carbohydrate from food and drink and turns it into glucose. However, when the glucose enters their bloodstream, there is no insulin that enables it to get into cells in the body. This causes glucose to build up in the bloodstream, leading to high blood sugar levels.


  1. Diabetes UK. Diabetes Statistics [Online]. Available at: https://www.diabetes.org.uk/professionals/position-statements-reports/s…. (Accessed 12th December 2022).
  2. NHS. Diabetes [Online]. Available at: https://www.nhs.uk/conditions/diabetes/. (Accessed 12th December 2022).


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