Condition4 min read
Prediabetes
Blood glucose is higher than normal but not high enough to be called diabetes. It usually causes no symptoms, and lifestyle change can reduce the chance of progressing to type 2 diabetes.
The NIDDK estimates that about 97.6 million US adults were at this stage in 2021. It is diagnosed with an A1C test (5.7–6.4%), fasting glucose (100–125 mg/dL) or a glucose tolerance test (140–199 mg/dL). The Diabetes Prevention Program showed that losing 5–7% of body weight reduced the risk of progressing to diabetes.
The NIDDK lists risk factors including excess weight, a large waist circumference, age 35+, family history, low physical activity, smoking, gestational diabetes, polycystic ovary syndrome, sleep apnoea and some medicines (glucocorticoids, antipsychotics and HIV medicines).
In one minute12
- What is it?
- Blood sugar higher than normal but not yet at the level for diagnosing diabetes.
- Who is usually affected?
- Common; about 97.6 million US adults in 2021 according to the NIDDK.
- Acute or chronic?
- May progress to type 2, and may be prevented or delayed by lifestyle change.
- Main symptoms
- Often no symptoms.
- Red flags?
- No special warning signs; intense thirst and frequent urination call for assessment for diabetes.
- Preventable?
- Losing 5–7% of weight and regular physical activity according to the Diabetes Prevention Program.
What is it?
It means blood sugar is higher than normal but has not reached the level for diagnosing type 2 diabetes.
According to the NIDDK about 97.6 million US adults had prediabetes in 2021, and this did not change much over 15 years.
Risk factors
Excess weight, obesity or a large waist circumference, age 35 or over, family history of diabetes, certain ethnic backgrounds, low activity, smoking and passive smoking, gestational diabetes or having a baby weighing 9 pounds or more, polycystic ovary syndrome, Cushing's syndrome, sleep apnoea, and some medicines.
Symptoms
No symptoms in most people, and some may have diabetes-like symptoms.
How is it diagnosed?
A1C test: 5.7% to 6.4%. Fasting glucose: 100 to 125 mg/dL. Glucose tolerance test: 140 to 199 mg/dL.
The NIDDK advises testing for people with risk factors, and for those who had gestational diabetes (6–12 weeks after delivery and then every 3 years).
Prevention
The Diabetes Prevention Program (DPP) showed that losing 5% to 7% of body weight reduced the risk of developing diabetes. Metformin also delayed the onset of type 2, especially in women with a history of gestational diabetes, younger people, and people with obesity (the medicine decision is for the doctor).
The NIDDK recommends at least 30 minutes of physical activity five days a week, smaller portions, lower-fat foods, and drinking water instead of sweetened drinks. The doctor may recommend metformin to prevent or delay diabetes, and this is discussed with the doctor.
When do you need urgent help?
Get urgent care today
- Intense thirst, frequent urination and blurred vision with weight loss: these may indicate diabetes needing prompt assessment.1
See your doctor within days
- Having risk factors (excess weight, family history, previous gestational diabetes) without a recent blood sugar or A1C test.1
Educational content only — no diagnosis, and no substitute for a clinician.
Common questions
Questions for your doctor
- What is my A1C, and should I repeat the test, and when?
- What target weight, diet pattern and activity suit me?
- Would I benefit from a structured prevention programme?
- Could any medicine I take raise my blood sugar?
References
- 1NIDDK / NIH. Insulin Resistance & Prediabetes. www.niddk.nih.gov/health-information/diabetes/overview/what-is-diabetes/prediabetes-insulin-resistanceHealth agencies & guidelines · Accessed 2026-10-03
- 2NIDDK / NIH. Preventing Type 2 Diabetes. www.niddk.nih.gov/health-information/diabetes/overview/preventing-type-2-diabetesHealth agencies & guidelines · Accessed 2026-10-03
Review status: Edited content · Last updated:
Change log
- — Page created.
Educational content only — no diagnosis, and no substitute for a clinician.