Evidence guide
What Causes Prediabetes? Insulin Resistance and Risk Factors Explained
Learn how insulin resistance can raise blood glucose, which risk factors are associated with prediabetes, and which factors you may be able to change.
Published 2026-08-20 · Updated 2026-08-20 · Author: Prediabetes.Life
Short answer
Prediabetes commonly develops when the body does not respond to insulin as effectively as it should and the pancreas can no longer fully compensate, allowing blood glucose to rise above the normal range. There is rarely one single cause. Age, family history, body weight or waist size, physical activity, pregnancy history, certain health conditions, smoking, and some medicines can all affect risk.
What is insulin resistance?
Insulin helps glucose move from the bloodstream into cells for energy. With insulin resistance, cells in muscle, fat, and the liver do not respond to insulin as well as they should. The pancreas may initially make more insulin to compensate. Over time, if compensation is not enough, blood glucose can rise into the prediabetes range.
Is prediabetes caused only by body weight?
No. Higher body weight or a larger waist can increase risk for many people, but they are not the only factors. Family history, age, physical activity, smoking, gestational diabetes, polycystic ovary syndrome, sleep apnea, and some medicines are among the factors NIDDK lists.
Which risk factors can I change?
- Increase physical activity gradually in a way you can sustain.
- Improve meal quality and portion patterns rather than relying on a short-term restrictive diet.
- Work toward a healthy weight if weight loss is appropriate for you.
- Avoid smoking and ask for help quitting if you use tobacco.
- Discuss sleep, medications, and other health conditions with your healthcare team.
Can someone develop prediabetes despite doing many things “right”?
Yes. Not every risk factor is controllable, and prediabetes is not a moral judgment. Genetics, age, prior pregnancy history, medical conditions, and medication exposure can influence risk. The useful question is which next actions are realistic for your situation.
Sources
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