Prediabetes affects a vast number of adults and represents a crucial opportunity for prevention: while blood glucose is elevated, it has not yet reached the threshold for a Type 2 diabetes diagnosis, meaning timely lifestyle changes can still make a major difference to long‑term health.
How widespread is it — and why it matters
The US Centres for Disease Control and Prevention estimates that roughly 88 million adults — about one in three — have prediabetes. Alarmingly, the majority do not realise they have the condition; the CDC puts the proportion of unaware people at around 84%. Left unchecked, prediabetes raises the odds of developing Type 2 diabetes and is associated with an increased risk of heart disease and stroke.
At its core, prediabetes reflects a reduced response to insulin. To compensate, the pancreas produces more of the hormone, but over time it may struggle to keep blood sugar within a normal range. Because symptoms are often subtle or absent, many people live with elevated glucose for years before problems are identified.
Who should consider testing
The CDC recommends that people speak to a clinician about having their blood sugar measured if they have one or more of the following risk factors. These are practical prompts for clinicians and the public alike to consider screening:
- Age 45 or older
- Overweight
- First‑degree relative with Type 2 diabetes
- Low levels of physical activity (less than three times per week)
- A history of gestational diabetes or delivery of a baby weighing more than 9 pounds (around 4.1kg)
- Polycystic ovary syndrome (PCOS)
- Membership of certain ethnic groups at higher risk — including African American, Hispanic/Latino, American Indian, Pacific Islander and some Asian American populations
Practical steps that work
Evidence and public health guidance converge on a few straightforward measures that can prevent or delay the onset of Type 2 diabetes among people with prediabetes. Key interventions promoted by the CDC and clinical bodies include:
- Achieving and maintaining modest weight loss — even a small reduction in body weight can lower risk
- Increasing regular physical activity — consistent exercise improves insulin sensitivity
- Adopting a healthier diet that reduces intake of saturated fats and refined carbohydrates
- Quitting smoking
To support lasting behaviour change, the CDC runs a National Diabetes Prevention Programme that provides structured coaching and peer support to help participants embed new habits over the long term.
Signs that diabetes may have developed
When prediabetes progresses to Type 2 diabetes, symptoms become more apparent. The Mayo Clinic highlights common warning signs to watch for, which include:
| Possible symptom | What it may indicate |
|---|---|
| Increased thirst | Raised blood sugar levels |
| Frequent urination | Body attempting to rid excess glucose |
| Excess hunger and fatigue | Disrupted glucose use by the body |
| Blurred vision | Potential damage to small blood vessels in the eye |
Because diabetes can harm the eyes and other organs, annual eye screening is advised for people with the condition.
Putting prevention into practice
For those diagnosed with prediabetes, the message is empowering: change is possible and effective. Talking to a healthcare professional about testing is the first step, particularly for people with the risk factors listed above. From there, enrolling in a structured prevention programme or making targeted lifestyle adjustments — such as shaving a few kilograms, moving more each day and improving dietary choices — can substantially reduce future health risks.
Public health initiatives, clinical screening and accessible prevention programmes together offer a realistic pathway to curb the progression from prediabetes to Type 2 diabetes and to lower the wider burden of cardiovascular disease.
