Last updated:

Reviewed by:

Dr Bryony Henderson

, Lead GP at Livi

Medically reviewed

Prediabetes is a condition in which you have raised blood sugar levels. These levels aren’t quite high enough to be classed as type 2 diabetes. Read on to find out more.

What is prediabetes?

Prediabetes is characterised by a rise in blood glucose levels. The difference between prediabetes and diabetes is that in prediabetes, the blood glucose level recorded is not high enough to lead to a diagnosis of type 2 diabetes. The levels of blood glucose are tested with a blood test. The most common test used to measure this is called HbA1c. It looks at your average sugar level over the past 3 months.

What are the symptoms of prediabetes?

You usually don’t have any symptoms with prediabetes. However, as your sugar levels increase in your blood to diabetic levels, you may have diabetic symptoms. These may include:

  • Feeling very thirsty

  • Peeing a lot, especially at night

  • Feeling tired and weak

  • Losing weight with no clear explanation

  • An itchy penis or vagina, or thrush

  • Cuts and grazes taking longer than usual to heal

  • Blurred vision

If you notice any of these symptoms, it is important you contact your doctor and arrange an appointment.

As there are often no warning signs of prediabetes, it is usually picked up on a blood test for something completely different.

How common is prediabetes?

It’s fairly common in the UK, with about 7 million people estimated to be living with prediabetes.

What causes prediabetes?

Prediabetes is caused by the same factors as type 2 diabetes. Like type 2 diabetes, there are lots of things that increase your chance of having prediabetes.

High blood sugar in prediabetes is caused by the body’s decreased response to insulin. A person’s body may become unresponsive to insulin for any number of reasons. A poor diet, lack of exercise, polycystic ovary syndrome and excessive alcohol intake are all associated with increased risk of prediabetes.

Who is at risk of prediabetes?

Some people are at higher risk of developing prediabetes than others. Factors that may increase your risk include:

  • Excessive alcohol intake

  • Lack of exercise

  • Being overweight

  • Family member with diabetes

  • Being older than 40

  • Having high blood pressure

  • Having high cholesterol levels

Prediabetes in children

Prediabetes is a lot more rare in children than in adults. As with adults, prediabetes in children has no symptoms as is usually only noticed on a blood test. If you are worried that your child may be at risk of prediabetes, contact your doctor and arrange an appointment.

How is prediabetes diagnosed?

Prediabetes is diagnosed by having a blood test, this type of test commonly looks for levels of HbA1c. This means it is looking at your average blood sugar levels for the last three months. The ranges for HbA1c are:

Prediabetes is between 42 mmol/mol and 47 mmol/mol

Diabetic is over 48 mmol/mol

How to prevent prediabetes

If you have been diagnosed with prediabetes, you are at increased risk of developing type 2 diabetes. Prediabetes, however, can be prevented in a number of ways. These include:

  • Eating a healthier diet

  • Exercising more

  • Drinking less alcohol

  • Lowering cholesterol levels

  • A healthy diet may include more:

  • Fruits and vegetables

  • Fish

  • Nuts and seeds

  • Whole Grain foods

It should include less:

  • Foods high in sugar like chocolate, sweets and cake

  • Foods high in saturated fats like butter and ice cream

  • Foods high in salt like crisps

  • Foods that are highly processed

  • Red meats

How is prediabetes treated?

Prediabetes is best treated with lifestyle changes as they can reverse the effects of prediabetes and prevent you developing type 2 diabetes.

If your blood glucose levels can’t be regulated with lifestyle changes, in some circumstances, you may be prescribed medication. This may include:

  • Metformin – tablets taken with or after meals

  • Other tablets – gliclazide, alogliptin, linagliptin, glimepiride or pioglitazone

  • Injections – exenatide or liraglutide

How long does prediabetes last?

Prediabetes lasts different lengths of time in different people. A number of people with prediabetes will, after their diagnosis, work on their lifestyle to then reverse the effects of prediabetes and take their blood sugars back to normal ranges. Others may stay prediabetic for a longer amount of time. Finally, some people with prediabetes will go on to develop type 2 diabetes.

When should I talk to a doctor?

If you are worried you may be at risk of prediabetes, get in contact with your doctor and they can arrange a blood test to look at your blood sugar levels.

How can Livi help?

A Livi doctor can talk to you about your symptoms and give you advice on the next best steps. They may suggest blood tests to look at your sugar levels. A livi doctor can also help with advice and tips for a healthier lifestyle.

Last updated:
Reviewed by:
Dr Bryony Henderson, Lead GP at Livi