What is the difference between type 1 and type 2 diabetes?

Type 1 diabetes

Type 1 diabetes is an autoimmune disease, which occurs when the immune system attacks and destroys the insulin-producing cells in the pancreas, called beta cells. As a result, the body cannot produce insulin, which is a hormone that helps regulate blood sugar levels. Type 1 diabetes can occur at any age.

The main treatment for type 1 is insulin.

Type 2 diabetes

Type 2 diabetes occurs when the body becomes resistant to insulin or doesn’t produce enough insulin to regulate blood sugar levels. This type of diabetes is often linked to lifestyle or family history and typically develops in adults over the age of 40, although it is becoming more common in younger adults and children.

Treatment for type 2 diabetes involves lifestyle changes such as regular exercise, a healthy diet, and weight loss, as well as medications to help lower blood sugar levels and insulin injections or other medications if needed.

Find out more about type 2 diabetes on the NHS website.

Other types of diabetes

There are several other types of diabetes. These include less common types such as latent autoimmune diabetes of adults (LADA), maturity onset diabetes of the young (MODY) and neonatal diabetes.

Gestational diabetes is another type of diabetes, which affects around one in 20 pregnancies.

Gestational diabetes

Gestational diabetes can occur during pregnancy. It is caused by hormonal changes that make the mother’s body less able to use insulin. As a result, glucose builds up in the blood, which can lead to high blood sugar levels and other complications for both the mother and the baby.

Gestational diabetes can increase the risk of certain complications, such as pre-eclampsia, premature delivery, and high birth weight, which can lead to problems during delivery and a higher risk of developing diabetes for both the mother and the child later in life.

Find out more about gestational diabetes on the NHS website.

Latent autoimmune diabetes of adults (LADA)

LADA has features of both type 1 and 2 diabetes, so is sometimes referred to as type 1.5 diabetes. People with LADA have biological markers that show their immune system is attacking their insulin-producing beta cells. These markers are also present in type 1, just at higher levels. This immune attack progresses slower in LADA than in type 1, so people with LADA often have hyperglycaemia at diagnosis that is less pronounced than in type 1.

This can lead to people with LADA being misdiagnosed with type 2 diabetes. Some people can manage LADA on diet, exercise and medication in the initial months or years following diagnosis, but most will move onto insulin therapy at some point.

Monogenic diabetes

Some rare forms of diabetes, known as monogenic diabetes, are caused by a problem with just one gene. Usually, this faulty gene is inherited from your parents, but sometimes it can develop randomly.

If you think you might have monogenic diabetes, a genetic test can confirm the diagnosis. Getting the correct diagnosis helps you make sure you’re getting the right treatment for you. People with monogenic diabetes don’t always need to take insulin, often taking diabetes tablets may be enough to manage your blood glucose levels.

The two most common types of monogenic diabetes are neonatal diabetes and maturity onset diabetes of the young. Find out more about monogenic diabetes.

Maturity onset diabetes of the young (MODY)

MODY is a type of diabetes which most commonly occurs in people under 25. People with MODY usually have family members with diabetes in each generation.

MODY is caused by one of several possible genetic mutations, with people experiencing different symptoms depending on which gene is affected. All the mutations make it more difficult for your pancreas to make insulin, leading to high blood sugar levels. MODY ranges from very mild and symptomless, through moderate forms which require diabetes medication, to more severe cases who require insulin. As with other types of diabetes, people with MODY may develop long-term complications due to raised blood sugar levels.

Neonatal diabetes

Neonatal diabetes is a type of monogenic diabetes in babies under six months, where a single gene mutation leaves them unable to make their own insulin.

Roughly half of people with neonatal diabetes have permanent neonatal diabetes, meaning they will have it for their whole lives. The other half have transient neonatal diabetes, which resolves itself after infancy, although it can come back later in life.

Babies with neonatal diabetes are often born much smaller and don’t grow at the same speed as other babies. They may also experience frequent urination, rapid breathing, and dehydration. It is often misdiagnosed as type 1 diabetes, but type 1 is incredibly rare in babies under six months. If this happens to your baby, you should ask your doctor for a genetic test.