What Is Prediabetes? Symptoms, Test Results and What to Do Next

14 September 202610 min readBy Keltoi Wellness

What Is Prediabetes? Symptoms, Test Results and What to Do Next

Prediabetes means that your blood glucose level is higher than normal, but not high enough to meet the diagnostic criteria for type 2 diabetes.

It is sometimes called non diabetic hyperglycaemia or being at high risk of type 2 diabetes. Prediabetes does not mean that developing diabetes is inevitable. For many people, it is an opportunity to identify the risk early and take practical steps to improve their health.

Quick Answer

Prediabetes is a blood glucose level above the normal range but below the level used to diagnose type 2 diabetes.

In the UK, an HbA1c result between 42 and 47 mmol/mol is generally considered to be within the prediabetes or high risk range. An HbA1c result of 48 mmol/mol or higher may indicate diabetes, although further assessment or repeat testing may be needed.

Prediabetes usually has no obvious symptoms. It is often discovered during a routine blood test or when someone is tested because they have risk factors for type 2 diabetes.

Healthy eating, physical activity, weight management where appropriate and regular monitoring can reduce the likelihood of prediabetes progressing.

What Happens When You Have Prediabetes?

The body uses a hormone called insulin to help move glucose from the bloodstream into cells, where it can be used for energy.

With prediabetes, the body may be becoming less responsive to insulin. This is known as insulin resistance. The pancreas may initially produce more insulin to compensate, but blood glucose can gradually begin to rise.

At this stage, blood glucose is higher than it should be, but it has not reached the level used to diagnose type 2 diabetes.

Prediabetes can remain stable, return to below the high risk range or progress to type 2 diabetes. What happens will differ between individuals.

Is Prediabetes the Same as Diabetes?

No.

Prediabetes means blood glucose is raised, but it remains below the diagnostic threshold for diabetes.

Type 2 diabetes means the body is no longer regulating blood glucose effectively enough to keep it below the diabetes range.

Prediabetes is also different from type 1 diabetes. Type 1 diabetes is an autoimmune condition in which the immune system attacks the cells that produce insulin. It is not caused by weight, diet or lifestyle.

What Is the Prediabetes HbA1c Range?

HbA1c is one of the main blood tests used to identify prediabetes and type 2 diabetes. It provides an indication of average blood glucose over approximately the previous two to three months.

The commonly used UK ranges are:

Below 42 mmol/mol: Below the prediabetes range
42 to 47 mmol/mol: Prediabetes or high risk of type 2 diabetes
48 mmol/mol or above: Within the diabetes range

A result within the diabetes range does not always confirm the diagnosis on its own. If someone does not have symptoms, a repeat blood test is usually required.

NICE also identifies a fasting blood glucose result between 5.5 and 6.9 mmol/L as being within the high risk range. NICE guidance on preventing type 2 diabetes

Blood results should be interpreted by a healthcare professional who understands your medical history and the reason for testing.

Can HbA1c Results Be Misleading?

HbA1c is useful, but it is not suitable in every situation.

Pregnancy, some types of anaemia, certain blood conditions, recent blood loss, kidney disease and other medical circumstances can affect the result or make another test more appropriate.

HbA1c may also be unsuitable when type 1 diabetes is suspected or symptoms have developed quickly.

Your doctor may use a fasting blood glucose test, an oral glucose tolerance test or repeat testing when HbA1c does not provide enough information.

Does Prediabetes Cause Symptoms?

Prediabetes usually causes no clear symptoms.

Many people feel completely well and only discover it after having a blood test. This is why testing may be offered to people with recognised risk factors.

Symptoms such as the following may indicate that blood glucose has risen further:

Feeling very thirsty
Passing urine more often, particularly during the night
Unexplained tiredness
Blurred vision
Losing weight without trying
Cuts or wounds taking longer to heal
Recurrent thrush or genital itching

Contact your GP if you develop possible symptoms of diabetes. Do not wait for a routine review if you are feeling increasingly unwell. NHS guidance on type 2 diabetes symptoms and diagnosis

Who Is More Likely to Develop Prediabetes?

Prediabetes can affect people with a wide range of body sizes and backgrounds. Risk tends to increase when several factors are present.

These may include:

Having a parent, brother or sister with type 2 diabetes
Being aged over 40, although it can develop earlier
Being of South Asian, Black African or African Caribbean background
Carrying excess weight, particularly around the waist
Having high blood pressure
Having a history of gestational diabetes
Having polycystic ovary syndrome
Being physically inactive
Having cardiovascular disease
Taking certain medicines that can affect blood glucose
Having previously been told that your blood glucose was raised

Genetics, hormones, medication, sleep, stress, environment and social circumstances can all influence risk. Prediabetes should not be reduced to a simple matter of willpower.

Can Prediabetes Be Reversed?

Some people can bring their blood glucose back below the prediabetes range.

The word reversed is commonly used, but it can give the impression that the risk has permanently disappeared. A more accurate description is that blood glucose has returned to below the high risk range.

Someone whose result improves may still have an increased chance of developing type 2 diabetes later. Continuing healthy habits and attending recommended blood tests remain important.

There is no guarantee that lifestyle changes will produce a particular result. Age, genetics, medical conditions and other individual factors may influence how blood glucose responds.

Does Prediabetes Always Become Type 2 Diabetes?

No. Progression is not inevitable.

Some people will develop type 2 diabetes, while others remain within the prediabetes range or see their blood glucose improve.

This makes early identification useful. There may be time to address relevant risk factors before glucose rises further.

Regular monitoring matters because prediabetes usually does not cause symptoms. Feeling well does not necessarily mean that the blood glucose level has returned to normal.

What Can Help Lower the Risk of Type 2 Diabetes?

The most helpful changes are usually those that can be maintained over time. An extreme or highly restrictive diet is not required.

Choose balanced, fibre rich meals

A practical meal may include:

Vegetables or salad
Beans, peas or lentils
Wholegrain bread, oats, brown rice or potatoes
Fish, eggs, poultry, yoghurt, tofu or another source of protein
A moderate amount of unsaturated fat

Carbohydrates do not need to be removed completely. The amount, type and overall balance of the meal are more useful considerations.

Sugary drinks, frequent sweets and heavily processed foods can contribute large amounts of sugar or energy without being very filling. Reducing these can be helpful, but having prediabetes does not mean that you can never eat sugar again.

Become more active

Physical activity helps muscles use glucose and can improve the body’s response to insulin.

UK guidance recommends that adults work towards at least 150 minutes of moderate intensity activity each week, together with muscle strengthening activity on at least two days.

Walking, cycling, swimming, gardening and active daily tasks can all count. Any increase from your current activity level may be beneficial.

If you have a medical condition, mobility difficulty or have not exercised for some time, ask a healthcare professional what activity is suitable for you.

Consider weight management where appropriate

For people carrying excess weight, a reduction in weight may improve insulin sensitivity and reduce the risk of developing type 2 diabetes.

This does not mean that everyone with prediabetes needs to lose weight. Risk should be assessed individually, and the focus should be on sustainable health changes rather than rapid weight loss.

Body weight is influenced by appetite, genetics, sleep, hormones, medication, stress, health conditions and previous dieting, as well as food and activity.

Protect sleep and manage stress

Poor sleep and prolonged stress can affect appetite, activity and blood glucose regulation.

Improving sleep will not replace medical care, but regular sleep routines and appropriate support for stress may form part of a wider prevention plan.

Stop smoking

Smoking increases the risk of cardiovascular disease and can add to the health risks associated with raised blood glucose.

A GP or pharmacist can advise on stop smoking support available locally.

Do You Need Medication for Prediabetes?

Most people with prediabetes are initially supported with lifestyle changes and monitoring.

NICE says that metformin may be considered for certain people at high risk, particularly when blood glucose has worsened despite participation in an intensive lifestyle programme or when someone cannot take part in such a programme.

Medication is not automatically required and is not suitable for everyone. Any decision to prescribe should be made by an appropriately qualified clinician after an individual assessment.

Do not take diabetes medication that has been prescribed for another person.

Do You Need to Check Your Blood Glucose at Home?

Most people with prediabetes do not need to check their blood glucose every day unless a healthcare professional specifically advises them to do so.

Home glucose meters show blood glucose at a particular moment. HbA1c gives a broader picture covering the previous two to three months.

Your GP or practice nurse can advise how often you should have a repeat blood test. The timing may depend on your original result, health, age, medication and other risk factors.

What Support Is Available in Northern Ireland?

Diabetes Prevention Programmes are available through several Health and Social Care Trusts in Northern Ireland.

These programmes support eligible adults with areas such as:

Healthy eating
Physical activity
Weight management
Behaviour change
Reducing the risk of type 2 diabetes

Access usually requires a referral from a GP practice following a recent blood test. Availability, programme arrangements and referral criteria can vary between Trust areas.

For example, the Northern Health and Social Care Trust lists an HbA1c of 42 to 47 mmol/mol or fasting glucose of 5.5 to 6.9 mmol/L within its referral criteria. Northern Trust Diabetes Prevention Programme

The South Eastern, Southern and Western Trusts also publish information about diabetes prevention support:

Speak to your GP practice to find out what is currently available in your area.

When Should You Contact Your GP?

Arrange a GP appointment if:

You have possible symptoms of diabetes
A private or workplace blood test has shown raised glucose
You previously had gestational diabetes
You have several risk factors and have not recently been tested
You are losing weight without trying
You feel persistently thirsty or are passing urine frequently
You have questions about a previous HbA1c result

Seek urgent medical advice if you become very unwell, particularly if you have vomiting, abdominal pain, rapid breathing, marked drowsiness or confusion.

Looking for Weight Management Support in Northern Ireland?

Keltoi Wellness provides doctor led remote weight management support for adults across Northern Ireland.

Prediabetes, blood pressure, medical history, medication and other health factors may be relevant during an individual weight management assessment. Keltoi provides the administrative and patient support element of the service, while clinical decisions are made independently by the treating doctor.

Where prescription treatment is considered, the final decision is made by an appropriately registered doctor. Treatment is not guaranteed and is only prescribed where clinically appropriate.

Keltoi does not replace routine diabetes monitoring through your GP. Anyone with prediabetes should continue attending recommended blood tests and medical reviews.

What Is Prediabetes? Symptoms, Test Results and What to Do Next