Prediabetes
Prediabetes: HbA1c, Blood Sugar Levels, Symptoms & How to Prevent Type 2 Diabetes
Written by Dr. Ajay V. Kaduskar, Diabetologist, Nagpur
MD (Medicine), PGDHSc (Diabetology), FEACD (The Netherlands)
Published · 12 to 15 minutes
Quick answer
Prediabetes is generally diagnosed when an HbA1c is 5.7% to 6.4%, fasting plasma glucose is 100 to 125 mg/dL, or the 2-hour glucose during a 75-g oral glucose tolerance test is 140 to 199 mg/dL. It usually does not cause clear symptoms. Prevention focuses on improving food quality, increasing physical activity, addressing excess weight when present, and following an appropriate monitoring plan.
Prediabetes means that your blood glucose is higher than the normal range, but it has not yet reached the level used to diagnose diabetes. The important part is that prediabetes often causes no obvious symptoms. A person can feel completely well and still have an abnormal HbA1c or blood glucose result.
That is why finding prediabetes is useful. It gives you an opportunity to look at your blood sugar, weight, food habits, physical activity and other risk factors before Type 2 diabetes develops.
Prediabetes does not mean that diabetes is inevitable. For many people, timely lifestyle changes and appropriate medical follow-up can substantially lower the risk of progression.
| Test | Normal range | Prediabetes range | Diabetes range |
|---|---|---|---|
| HbA1c | Below 5.7% | 5.7 to 6.4% | 6.5% or above |
| Fasting blood glucose | Below 100 mg/dL | 100 to 125 mg/dL | 126 mg/dL or above |
| 2-hour OGTT glucose | Below 140 mg/dL | 140 to 199 mg/dL | 200 mg/dL or above |
These ranges apply to non-pregnant adults; pregnancy uses different diagnostic criteria.
What is prediabetes?
Prediabetes is a state in which blood glucose levels are above the usual healthy range but below the diagnostic threshold for diabetes.
It is often associated with insulin resistance. In simple terms, insulin is a hormone that helps glucose move from the bloodstream into cells. When the body's tissues become less responsive to insulin, the pancreas has to produce more insulin to maintain normal glucose levels.
Over time, this compensation may become less effective, and blood glucose begins to rise.
Prediabetes is therefore not simply a slightly abnormal blood test. It can be a sign that the body's glucose-regulation system is under increasing metabolic stress.
At the same time, a diagnosis of prediabetes should not be viewed as a prediction that you will definitely develop diabetes. Risk varies from person to person.
What HbA1c level means you have prediabetes?
An HbA1c of 5.7% to 6.4% falls within the prediabetes range.
HbA1c is different from a single blood glucose reading. It reflects your average blood glucose exposure over roughly the previous two to three months.
For example, someone may have a fasting glucose that looks acceptable on one morning but still have an elevated HbA1c. Conversely, an isolated high glucose result does not automatically tell the whole story.
How to understand the HbA1c number
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Below 5.7%: generally below the prediabetes range
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5.7% to 6.4%: prediabetes range
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6.5% or higher: diabetes range
A result close to a diagnostic threshold may require appropriate confirmation and clinical interpretation. In people without unequivocal hyperglycaemia, diabetes generally requires confirmation with repeat testing or another abnormal diagnostic test.
Your HbA1c should therefore be interpreted in context rather than treated as a number that tells you everything about your health.
What blood sugar level is considered prediabetes?
Prediabetes can be identified using more than one glucose test.
Fasting blood sugar
A fasting glucose of 100 to 125 mg/dL is in the prediabetes range.
The test is usually performed after an appropriate period without eating, as instructed by the laboratory or clinician.
Two-hour glucose test
During a 75-g oral glucose tolerance test, a 2-hour glucose value of 140 to 199 mg/dL falls in the prediabetes range.
Why can different tests give different results?
HbA1c and glucose tests measure different aspects of glucose metabolism. It is therefore possible for someone to have a result in the prediabetes range on one test and a different result on another.
Rather than trying to interpret each number independently, discuss the overall pattern with your doctor.
Does prediabetes have symptoms?
Often, no.
This is one of the reasons prediabetes can go unnoticed.
Some people may report symptoms such as tiredness or increased hunger, but these symptoms are not specific enough to diagnose prediabetes. Many people discover the condition only after a routine blood test.
This is also why waiting for symptoms is not a reliable way to decide whether you should be tested.
If you have risk factors for diabetes, periodic screening can identify changes before symptoms become apparent.
Why does prediabetes happen?
There is rarely one single cause.
Prediabetes can develop through a combination of genetic, metabolic and lifestyle factors. Insulin resistance is an important part of the process for many people.
Factors that can increase risk include:
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Excess body weight, particularly abdominal fat
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Low physical activity
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A family history of Type 2 diabetes
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Increasing age
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Previous gestational diabetes
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High blood pressure
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Abnormal cholesterol or triglyceride levels
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Conditions associated with insulin resistance
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Certain medications or medical conditions
Not everyone with prediabetes has the same combination of risk factors.
Who is at higher risk of prediabetes?
You may have a higher risk if diabetes runs in your family or if you have several metabolic risk factors.
It is worth discussing screening with a doctor if you have:
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A parent or sibling with Type 2 diabetes
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Overweight or obesity
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High blood pressure
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Abnormal cholesterol levels
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A history of gestational diabetes
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Limited physical activity
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Previous abnormal blood glucose results
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Other conditions associated with insulin resistance
Risk assessment should not be based on body weight alone.
Why is prediabetes important for Indians?
South Asian populations can develop Type 2 diabetes and metabolic abnormalities at lower levels of body weight than might be expected from conventional assumptions based only on obesity.
That makes metabolic risk particularly relevant when assessing an Indian patient.
Someone who does not consider themselves overweight can still have insulin resistance, abdominal fat, abnormal lipids or elevated blood glucose.
This is one reason routine screening should be based on the individual's overall risk profile rather than appearance alone.
How is prediabetes diagnosed?
Prediabetes is diagnosed through blood testing.
Common tests include:
HbA1c
This measures glycated haemoglobin and provides an estimate of average blood glucose over the preceding few months.
Fasting plasma glucose
This measures blood glucose after fasting.
Oral glucose tolerance test
This involves measuring glucose before and after consuming a standard glucose drink.
A doctor may choose one test or more than one depending on the person's circumstances.
It is also important to understand that one abnormal result does not always tell the complete story. The test used, laboratory conditions, symptoms, medical history and whether confirmation is required all matter.
What should you do after being diagnosed with prediabetes?
The first step is not panic.
The diagnosis is an opportunity to identify the factors contributing to your blood glucose level and decide what needs to change.
A useful medical assessment may include looking at:
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HbA1c and glucose readings
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Blood pressure
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Weight and waist measurements
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Lipid profile
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Family history
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Physical activity
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Eating patterns
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Sleep and other lifestyle factors
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Other conditions associated with metabolic risk
From there, your doctor can help decide how frequently you need monitoring and whether lifestyle intervention alone is appropriate or whether additional treatment should be considered.
Can prediabetes be prevented from becoming Type 2 diabetes?
In many people, the risk can be reduced substantially.
The strongest approach is usually not one dramatic change. It is a collection of manageable changes that can be maintained over time.
For adults with overweight or obesity who are at high risk, the 2026 ADA Standards recommend a structured lifestyle approach that aims for around 5 to 7% weight loss, where appropriate, together with at least 150 minutes of moderate-intensity physical activity per week.
That does not mean everyone with prediabetes needs to lose weight.
If you are already at a healthy weight, the focus may instead be on food quality, activity, sleep, muscle strength and other metabolic risk factors.
What should you eat if you have prediabetes?
There is no single food plan that works for every person with prediabetes.
The goal is to build a pattern of eating that supports blood glucose control and is realistic enough to follow over the long term.
For many people, this means giving more space to:
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Non-starchy vegetables
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Whole fruits
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Pulses and legumes
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Whole grains
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Nuts and seeds
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Lean protein sources
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Appropriate portions of dairy or alternatives
At the same time, it is useful to reduce frequent intake of:
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Sugary drinks
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Sweets and desserts
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Refined grains
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Highly processed foods
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Foods that are very high in calories but low in nutritional value
The ADA emphasizes overall dietary quality and individualized nutrition rather than a single universal diet.
Do you have to stop eating rice or roti?
Not necessarily.
For an Indian household, completely removing staple foods may not be practical or necessary. Portion size, preparation, the type of carbohydrate, protein, vegetables and the overall meal pattern all matter.
A plate containing a large portion of rice with very little protein or vegetables is different from a balanced meal containing a more moderate carbohydrate portion alongside vegetables and protein.
The right approach depends on your overall health, glucose levels, dietary habits and goals.
How does exercise help with prediabetes?
Regular physical activity helps the body use glucose more effectively.
You do not need to begin with an intense workout routine.
Walking, cycling, swimming, resistance training and other activities can all have a place in a prevention plan.
A practical target for many adults is at least 150 minutes of moderate-intensity physical activity each week, provided there is no medical reason to restrict exercise. Resistance training can also be useful.
Breaking up long periods of sitting is another simple habit worth considering.
The important point is consistency. A realistic routine performed regularly is usually more useful than an ambitious exercise plan that lasts only a few weeks.
Does weight loss help prediabetes?
If you have overweight or obesity, even a moderate amount of weight loss can improve glucose metabolism and other cardiometabolic risk factors.
For people at high risk, a target of approximately 5 to 7% reduction in body weight is used in structured diabetes-prevention approaches.
For example, a person weighing 80 kg would reach 5% weight loss after losing about 4 kg.
But the number on the scale is not the only outcome that matters.
Changes in waist circumference, blood glucose, blood pressure, fitness and metabolic health can also be clinically meaningful.
And if your weight is already in a healthy range, deliberately losing weight may not be appropriate. Prevention should be individualized.
Is medicine ever used for prediabetes?
Lifestyle intervention is an important part of prediabetes management, but medication may be considered for selected people at particularly high risk.
For example, the ADA notes that metformin may be considered in certain high-risk adults, including some younger adults with obesity, higher glucose or HbA1c levels, or a history of gestational diabetes.
That does not mean everyone with prediabetes should take metformin.
The decision depends on the individual's risk profile, medical history, laboratory results and other factors.
Do not start, stop or change diabetes medication based solely on information found online.
How often should you test for diabetes if you have prediabetes?
People with prediabetes generally need regular follow-up rather than a one-time test.
The ADA recommends annual testing for people with prediabetes, although your doctor may recommend a different interval depending on your individual risk and previous results.
Follow-up is useful because blood glucose can change over time.
A repeat HbA1c may show improvement, stability or progression. The result should be considered alongside your weight, lifestyle, medications and other health measurements.
What happens if prediabetes is ignored?
Prediabetes does not automatically become diabetes.
But it is associated with an increased risk of developing Type 2 diabetes, particularly when several risk factors are present.
It may also occur alongside other cardiometabolic problems such as high blood pressure, abnormal cholesterol and excess abdominal fat.
The purpose of identifying prediabetes is therefore not to label someone as "almost diabetic." It is to identify an opportunity for prevention and risk reduction.
Prediabetes vs Type 2 diabetes
| Feature | Prediabetes | Type 2 Diabetes |
|---|---|---|
| Blood glucose | Above normal | In the diabetes range |
| HbA1c | 5.7 to 6.4% | ≥6.5% |
| Symptoms | Often absent | May or may not be present |
| Can it improve? | Often with lifestyle and risk-factor management | Blood glucose can often be improved substantially, but ongoing management is usually required |
| Monitoring | Regular follow-up | Long-term monitoring |
| Prevention focus | Reduce progression risk | Control glucose and reduce complications |
The diagnostic thresholds above are based on current ADA criteria for non-pregnant adults.
Common myths about prediabetes
Myth 1: "prediabetes means i already have diabetes."
No. Prediabetes and diabetes have different diagnostic ranges. However, prediabetes is a meaningful warning sign that deserves attention.
Myth 2: "if i feel fine, my sugar must be normal."
Not necessarily. Prediabetes frequently has no noticeable symptoms.
Myth 3: "i need to stop eating carbohydrates completely."
No. Carbohydrates can be part of a healthy diet. Portion size, food quality and the overall meal pattern are more important than simply banning an entire food group.
Myth 4: "only people with obesity get prediabetes."
No. Body weight is only one part of metabolic risk.
Myth 5: "once i have prediabetes, diabetes is unavoidable."
No. Risk is increased, but progression is not inevitable. Lifestyle changes and appropriate medical follow-up can help reduce risk.
Myth 6: "one normal sugar test means i do not need another test."
Not always. Different tests provide different information, and your future screening schedule should depend on your overall risk.
When should you see a doctor about prediabetes?
Consider a medical evaluation if:
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Your HbA1c is in the prediabetes range.
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Your fasting glucose is repeatedly elevated.
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You have several diabetes risk factors.
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Diabetes runs strongly in your family.
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You have previously had gestational diabetes.
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You have unexplained changes in weight or metabolic health.
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You have already been told that your blood sugar is abnormal and need a prevention plan.
If you develop symptoms such as marked thirst, frequent urination, unexplained weight loss, significant weakness, vomiting, confusion or other concerning symptoms, seek medical assessment rather than assuming they are simply due to prediabetes.
What to remember
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Prediabetes means blood glucose is higher than normal but below the diabetes range.
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HbA1c of 5.7 to 6.4% is in the prediabetes range.
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Prediabetes often causes no obvious symptoms.
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Family history, excess weight, inactivity and other metabolic risk factors can increase risk.
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You do not necessarily need to eliminate rice, roti or carbohydrates completely.
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Regular physical activity is an important part of prevention.
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If overweight or obesity is present, even moderate weight loss may improve metabolic health.
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Some high-risk people may benefit from medication such as metformin under medical supervision.
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Regular follow-up helps identify whether blood glucose is improving, remaining stable or progressing.
A prediabetes diagnosis is worth taking seriously, but it does not need to become a source of constant worry.
For many people, this is the stage at which relatively practical changes can make a meaningful difference. The focus should be on understanding why the blood glucose is elevated, identifying the risk factors that can be changed, and creating a plan that fits everyday life.
You do not need to overhaul everything overnight.
A sustainable eating pattern, regular movement, appropriate weight management when needed and periodic blood tests can form the foundation of diabetes prevention.
If your HbA1c or blood glucose has recently come back abnormal, discussing the result with a doctor can help you understand what it means in the context of your overall health.
Sources and further reading
Frequently asked questions
An HbA1c of 5.7% to 6.4% falls within the prediabetes range for non-pregnant adults. An HbA1c of 6.5% or higher is within the diabetes range, although a diabetes diagnosis generally requires appropriate confirmation when there is no unequivocal hyperglycaemia.
Prediabetes can improve, and some people return to a blood glucose range below the prediabetes threshold. Improvements may occur with changes in physical activity, eating habits, weight management when appropriate and treatment of other metabolic risk factors. Continued monitoring is still important because glucose levels can rise again.
No. Prediabetes commonly has no clear symptoms. A person may feel completely well while having an elevated HbA1c or fasting glucose level. This is why blood testing is important for people who have relevant diabetes risk factors.
Rice does not automatically need to be eliminated. The amount, type of rice, meal composition and overall eating pattern matter. Combining a sensible carbohydrate portion with vegetables, protein and other nutrient-rich foods can be more practical than completely avoiding traditional staples.
For many adults at high risk of diabetes, structured prevention programs aim for at least 150 minutes of moderate-intensity physical activity per week. The appropriate amount and intensity depend on your age, fitness, medical conditions and current activity level.
Yes, prediabetes increases the risk of developing Type 2 diabetes, but progression is not inevitable. Risk varies between individuals. Lifestyle changes, appropriate weight management, regular physical activity and medical follow-up can help reduce the risk.
Not everyone does. Lifestyle intervention is central to prevention. Medication such as metformin may be considered for selected people at particularly high risk, depending on factors such as age, BMI, glucose levels, HbA1c and previous gestational diabetes.
The ADA recommends testing people with prediabetes at least annually, although the appropriate interval can vary according to individual risk and previous results. Your doctor may recommend more frequent monitoring when there is a reason to do so.
Related reading
- Prediabetes HbA1c: What the Number Means
- Can Prediabetes Go Away? How to Lower Your Risk
- Prediabetes Diet: What to Eat in an Indian Diet
- Prediabetes and Weight Loss: How Much Helps?
- How Often to Test for Diabetes With Prediabetes
Related guides: Diabetes Diet for Indians, Metabolic Syndrome, Fatty Liver & Cardiometabolic Health
If you would like advice suited to your own reports and medicines, you can book an appointment or visit Niramay Clinics in Dhantoli, Nagpur.
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