Millions of American adults have prediabetes, and the majority do not know it, according to estimates from the Centers for Disease Control and Prevention. Prediabetes means your blood sugar is higher than it should be but not high enough to be diagnosed as type 2 diabetes. It is a warning light on the dashboard rather than a final destination. With changes in daily habits, many people can lower their blood sugar and reduce the chance of developing diabetes. This guide covers what prediabetes is, how it is found, and what you can do.
This article is general information and not medical advice. Ask your clinician about testing and a plan tailored to you.
What is prediabetes?
When you eat, your body breaks carbohydrates down into glucose, a sugar that fuels your cells. The pancreas releases insulin, a hormone that helps glucose move from the blood into cells. In prediabetes, cells respond less well to insulin, a problem called insulin resistance, and the pancreas has to work harder. Blood glucose then begins to creep up.
Over time, if the pancreas cannot keep up, blood sugar rises into the diabetes range. Type 2 diabetes can damage blood vessels, nerves, kidneys, and eyes, and it raises the risk of heart disease and stroke. Even prediabetes has been linked to an increased risk of heart disease.
Symptoms and warning signs
Most people with prediabetes have no symptoms. That is why testing matters. Some people may notice:
- Darkened, velvety patches of skin, often on the neck, armpits, or groin, a sign called acanthosis nigricans that suggests insulin resistance.
- Increased thirst or urination, though these are more common once blood sugar is higher.
- Fatigue.
- Blurred vision.
Do not wait for symptoms. If you have risk factors, ask for a blood test.
Who is at risk?
Risk factors for prediabetes and type 2 diabetes include:
- Being overweight or having obesity, especially with extra weight around the abdomen.
- Age 45 or older, although it is increasingly common in younger people.
- A parent or sibling with type 2 diabetes.
- Physical inactivity.
- A history of gestational diabetes or giving birth to a baby over nine pounds.
- Polycystic ovary syndrome (PCOS).
- High blood pressure or abnormal cholesterol and triglycerides.
- Certain racial and ethnic backgrounds with higher risk, including Black, Hispanic or Latino, American Indian, Alaska Native, Pacific Islander, and some Asian American groups.
- Sleep problems, such as sleep apnea or chronic short sleep.
- Use of some medications, such as certain steroids and antipsychotics.
How prediabetes is diagnosed
Three common blood tests are used. The American Diabetes Association lists these general ranges:
| Test | Normal | Prediabetes | Diabetes |
|---|---|---|---|
| Hemoglobin A1C | Below 5.7% | 5.7% to 6.4% | 6.5% or higher |
| Fasting plasma glucose | Below 100 mg/dL | 100 to 125 mg/dL | 126 mg/dL or higher |
| Oral glucose tolerance test (2 hours) | Below 140 mg/dL | 140 to 199 mg/dL | 200 mg/dL or higher |
The A1C test reflects your average blood sugar over about two to three months and does not require fasting. Results should usually be confirmed with repeat testing. Some conditions, such as anemia, can affect A1C accuracy, so your clinician may choose another test.
Screening is commonly recommended for adults with overweight who have additional risk factors, and for many adults beginning around age 35 to 45, with repeat testing at intervals determined by results. Ask your clinician when you should be tested.
Can prediabetes be reversed?
For many people, yes, or at least delayed. A major U.S. research study, the Diabetes Prevention Program, found that participants with prediabetes who made lifestyle changes, including losing a modest amount of weight and exercising regularly, substantially reduced their chances of developing type 2 diabetes compared with a control group. The benefits were larger than those seen with medication in the same study. Results vary, and some people have a genetic predisposition that makes it harder, but the effort is worthwhile.
What helps
Lose a modest amount of weight if you are overweight
Losing about 5 to 7 percent of body weight can make a significant difference. For a person who weighs 200 pounds, that is about 10 to 14 pounds. Slow, steady loss is more sustainable than crash diets.
Move regularly
Aim for at least 150 minutes per week of moderate activity, such as brisk walking. You can break it into 30 minutes, five days a week, or shorter bouts of 10 minutes. Add strength training two or more times a week, since muscles use glucose and improve insulin sensitivity. Even short walks after meals may help lower blood sugar for some people.
Improve your eating pattern
There is no single required diet. Evidence supports several approaches, including Mediterranean-style and plant-forward eating. Common principles include:
- Choose whole grains rather than refined grains.
- Fill half your plate with non-starchy vegetables.
- Include lean protein, beans, nuts, fish, and healthy fats.
- Limit sugary drinks, which cause rapid blood sugar spikes. Replace them with water, unsweetened tea, or sparkling water.
- Limit sweets, pastries, and highly processed snacks.
- Watch portion sizes of rice, pasta, bread, and potatoes.
- Increase fiber, which slows sugar absorption.
A registered dietitian can create a plan that fits your culture, budget, and preferences. Many insurance plans and Medicare cover nutrition counseling for some conditions.
Sleep and manage stress
Chronic sleep loss and high stress can worsen insulin resistance. Aim for seven or more hours of sleep, and consider treatment if you have symptoms of sleep apnea.
Stop smoking and limit alcohol
Smoking increases diabetes risk and complications. Heavy alcohol use can affect blood sugar and weight.
Consider a structured program
The National Diabetes Prevention Program, led by the CDC, offers year-long lifestyle change programs through community organizations, health systems, and online providers. Participants work with a trained coach in a group to build habits. Medicare covers a version for eligible beneficiaries, and many employers and insurers offer coverage. Ask your clinician or insurer about a program near you.
What about medication?
For some people at high risk, especially those with a body mass index of 35 or higher, those under 60, or women with a history of gestational diabetes, clinicians may consider metformin. Other medications may be considered in certain situations. These decisions are individualized, and lifestyle change remains the foundation. Do not start or stop medication without medical guidance.
Monitoring your progress
- Repeat blood tests as advised, often yearly or more often depending on your results.
- Track habits such as steps, weight, and food choices if it helps.
- Check blood pressure and cholesterol, since heart risks cluster together.
- Keep up with eye exams, dental care, and foot checks if you are diagnosed with diabetes later.
Common myths
- “Prediabetes is not a big deal.” It raises the risk of diabetes and heart disease, and it is the best time to act.
- “Only overweight people get it.” Weight is a major risk factor, but people of any size can develop it.
- “Eating sugar causes diabetes.” Sugary foods and drinks contribute to weight gain and blood sugar spikes, but diabetes risk is multifactorial.
- “If I feel fine, I’m fine.” Most people with prediabetes feel normal.
Frequently Asked Questions
Does prediabetes always turn into diabetes?
No. Many people never develop type 2 diabetes, especially when they adopt healthier habits.
How fast can I lower my A1C?
Some people see improvement within three to six months of sustained changes. Your clinician can monitor your progress.
Do I have to give up carbohydrates?
Not necessarily. Focus on the quality, portion, and timing of carbohydrates, and choose fiber-rich options.
Are artificial sweeteners safe for prediabetes?
Evidence is mixed. Replacing sugary drinks with water is a clear benefit, and you can discuss sweeteners with your clinician or dietitian.
Can children get prediabetes?
Yes. Rates in children and teens with overweight have increased. Pediatricians can advise on screening.
The bottom line
Prediabetes is common, usually silent, and often reversible. If you have risk factors, ask about a blood test, and if the result is elevated, start with realistic changes in food, activity, and sleep. Small steps taken now can protect your long-term health.
