Skip to main content

Warning notification:Warning

Unfortunately, you are using an outdated browser. Please, upgrade your browser to improve your experience with HSE. The list of supported browsers:

  1. Chrome
  2. Edge
  3. FireFox
  4. Opera
  5. Safari

Pre-diabetes

Pre-diabetes means that your blood glucose levels (sugar) are higher than usual. But they are not high enough to diagnose you with type 2 diabetes.

Pre-diabetes means that you are at high risk of developing type 2 diabetes, heart disease and stroke.

The earlier pre-diabetes is diagnosed the better. You can treat pre-diabetes. This can prevent or delay type 2 diabetes.

Being active, reaching a healthy weight and eating healthy food can all reduce your risk of type 2 diabetes.

If you have pre-diabetes you should visit your doctor every year to monitor your blood glucose levels.

Symptoms of pre-diabetes

Many people have pre-diabetes without realising it because they do not have signs or symptoms.

You may develop high blood glucose levels over time without noticing.

You may already have type 2 diabetes.

Symptoms of type 2 diabetes

Who is at risk of pre-diabetes

You're more at risk of pre-diabetes if you:

  • are over 45
  • have a close relative with diabetes such as a parent, brother or sister
  • are an adult who has obesity or overweight
  • had gestational diabetes during pregnancy
  • are physically inactive - for example, if you take less than 30 minutes of physical activity 5 days per week
  • have high blood pressure, high cholesterol, low-HDL cholesterol or high triglycerides
  • have a history of heart disease
  • have a medical condition that needs long-term steroid use
  • are a member of the Travelling community
  • are of south Asian, Chinese, Hispanic, African, Caribbean or black African origin
  • have haemochromatosis - storing too much iron in your body
  • are a woman with polycystic ovary syndrome (PCOS)

Diagnosing pre-diabetes

Contact your GP if you have any symptoms of diabetes or you're worried you may have a risk of getting it.

They can do a blood test (called HbA1c) to check your blood glucose levels. It usually takes a few days for the results to come back.

The results of your test will show if you have:

  • no diabetes (less than 42mmol/mol)
  • pre-diabetes (42 to 47mmol/mol)
  • type 2 diabetes (48mmol/mol)

Mmol/mol stands for 'millimoles per mole'.

What your GP or nurse will discuss with you will depend on:

  • the results of your blood test
  • your risk of developing type 2 diabetes
  • if you have any other medical conditions

If you’re diagnosed with pre-diabetes, ask your doctor about:

  • what pre-diabetes is and what it means for your health
  • your risk of developing type 2 diabetes and your role in trying to prevent or delay it
  • what high blood glucose levels means for your health
  • eating well, being active and losing weight if you need to
  • medicines that may be needed to treat any other risks you may have for example, high cholesterol or high blood pressure
  • your lifestyle choices, such as smoking and drinking alcohol

Treatment for pre-diabetes

To treat pre-diabetes, try to:

Act now to help delay and prevent type 2 diabetes.

Diabetes Prevention Programme

The Diabetes Prevention Programme helps people with pre-diabetes to make healthy lifestyle changes.

It is a group course, and it runs for 12 months. You can take part online or in person. It is free.

Your GP can refer you to a programme running near you.

Watch a video about the Diabetes Prevention Programme (video)

Diabetes Prevention: A guide to healthy living (PDF, 32 pages, 3.2 MB)

Be more active

Being active brings benefits to treating diabetes and protecting your health. It can lower your blood glucose, blood pressure and cholesterol and manage weight.

How to increase your activity levels

Managing your weight

Having a healthy weight can help to delay or prevent type 2 diabetes.

Putting on extra weight (body fat) and being inactive are a major cause of developing pre-diabetes and type 2 diabetes.

Losing between 5 to 7% of your body weight can really help to prevent type 2 diabetes.

Speak to your GP if you:

  • need advice managing your weight
  • feel your weight is putting you at risk of type 2 diabetes

Check your body mass index (BMI)

Your BMI will help you find out if you are a healthy weight for your height.

Calculate your BMI online. You'll need to know your height, weight and waist size.

Check your BMI - safefood.net

Your GP or practice nurse can also measure it for you.

Check your waist size

Carrying a lot of weight (body fat) around your tummy can affect the way your pancreas and liver work. This increases your risk of developing diabetes.

Check your waist size to see if you are carrying any excess weight around your tummy. Do this even if your BMI is not too high.

Your risk of developing health problems increases if:

  • you are a man and your waist size is 94cm (37 inches) or more, (90cm or 35 inches or more if you are a man of Asian descent)
  • you are a woman and your waist size is 80cm (31.5 inches) or more

If you are overweight or carrying weight around the tummy area:

  • try to avoid gaining any more weight
  • look at what changes you could make to your diet
  • consider writing down what you eat and drink for a day or two to help identify possible changes you could make
  • consider weighing yourself once a week to help keep you focused and monitor your progress - a good time is first thing in the morning, with no shoes and in light or no clothing
  • be more active

Eat healthy food

To help prevent type 2 diabetes:

  • choose a healthy diet
  • learn how carbohydrates affect your blood glucose level
  • eat starchy, high fibre foods at each meal, for example wholemeal bread, wholegrain cereals, potatoes, wholegrain rice or pasta
  • choose foods that you enjoy, make changes that you can keep for the long term

Read more about eating well


Content supplied by the NHS and adapted for Ireland by the HSE

Page last reviewed: 13 November 2023
Next review due: 13 November 2026

This project has received funding from the Government of Ireland’s Sláintecare Integration Fund 2019 under Grant Agreement Number 9.