prediabetes

Prediabetes is the yellow light between the green of normal blood sugar and the red of diabetes. Glucose levels are higher than they should be but not yet high enough to be called diabetes — a warning that the body's sugar control is starting to slip, and a window in which the slide can often still be slowed or reversed.

Prediabetes describes blood glucose that sits above normal but below the diabetic threshold. It is defined by an impaired fasting glucose of 5.6–6.9 mmol/L (100–125 mg/dL), an impaired glucose tolerance with a 2-hour value of 7.8–11.0 mmol/L (140–199 mg/dL), or an HbA1c of 5.7–6.4%. Underlying it are early insulin resistance and the first hints of beta-cell strain.

People with prediabetes are at high risk of progressing to type 2 diabetes — many do within a few years — and even at this stage carry an increased risk of cardiovascular disease. The encouraging news is that intensive lifestyle change (modest weight loss and regular physical activity) substantially lowers the chance of progression, and metformin can help in higher-risk individuals. Prediabetes is therefore best seen not as a diagnosis to fear but as an opportunity to act.