Prediabetes usually has no symptoms at all. That’s the most important thing to know, and it’s exactly why the condition is so easy to miss. More than 115 million American adults have prediabetes, and 8 in 10 of them don’t know it. You can live with elevated blood sugar for years before anything feels different, which is why blood testing is the only reliable way to catch it.
That said, some people do notice subtle physical changes that point to insulin resistance, the underlying problem driving prediabetes. Recognizing those signs can prompt you to get tested sooner rather than later.
Why Prediabetes Is Usually Silent
Prediabetes means your blood sugar is higher than normal but not yet high enough to qualify as type 2 diabetes. On an A1C test, the prediabetic range falls between 5.7% and 6.4%. At these levels, your body is still compensating. Your pancreas may be producing extra insulin to keep blood sugar somewhat in check, and your kidneys aren’t yet overwhelmed by excess glucose. The result is that the classic diabetes warning signs, like constant thirst and frequent urination, typically don’t appear until blood sugar climbs higher.
The absence of symptoms doesn’t mean nothing is happening. Insulin resistance is already placing extra strain on your pancreas, blood vessels, and other tissues. Damage can accumulate quietly for years before you feel it.
Subtle Signs That Can Appear
While most people with prediabetes feel perfectly fine, a handful of physical changes are linked to the insulin resistance that underlies the condition.
Dark, Velvety Skin Patches
One of the most visible early signs is a skin condition called acanthosis nigricans: dark, thick, velvety patches that develop slowly in body folds and creases. The armpits, groin, and back of the neck are the most common locations. The affected skin may also feel itchy, develop an odor, or sprout small skin tags. Most people who develop these patches have become resistant to insulin, making it a strong visual clue worth mentioning to a doctor.
Skin Tags
Small, soft flaps of skin that hang from the body (particularly around the neck, armpits, and eyelids) have been linked to insulin resistance. Research has found that people with multiple skin tags have a higher risk of diabetes, and some clinicians treat a cluster of skin tags as a reason to screen for blood sugar problems. A few skin tags are common and don’t necessarily signal anything, but a sudden increase in their number is worth noting.
Fatigue, Especially After Meals
When insulin isn’t working efficiently, sugar stays in your bloodstream instead of entering your cells where it’s needed for energy. Your cells are essentially underfed even though your blood sugar is elevated. This can show up as persistent tiredness or a heavy, sluggish feeling after meals. Many people chalk this up to poor sleep or aging, but if it’s a recurring pattern alongside other risk factors, it may reflect early metabolic changes.
Blurred Vision
Elevated blood sugar can cause the lenses of your eyes to swell with fluid, temporarily distorting your vision. This is more common once blood sugar reaches diabetic levels, but some people in the prediabetic range notice occasional blurriness, particularly after high-carbohydrate meals. The effect is usually temporary and reverses when blood sugar drops.
When Symptoms Become More Obvious
The classic warning signs most people associate with diabetes, constant thirst, frequent urination, and increased hunger, generally mean blood sugar has already crossed into the diabetic range. These symptoms follow a specific chain reaction: when blood sugar stays high, your kidneys pull extra water from the blood to flush out the excess glucose, producing larger and more frequent amounts of urine. That fluid loss triggers dehydration, which makes you intensely thirsty. Even after drinking, the thirst doesn’t fully resolve because the cycle keeps repeating as long as blood sugar remains elevated. Meanwhile, because your cells aren’t absorbing glucose well, your body signals for more food, driving increased hunger.
If you’re experiencing these symptoms regularly, it’s likely that prediabetes has already progressed. But waiting for them to appear means missing the window where intervention is easiest.
Who Should Get Tested
Because symptoms are unreliable, risk factors matter more for deciding when to screen. The major ones include being overweight (especially carrying weight around the midsection), being over 45, having a family history of type 2 diabetes, being physically inactive, and having a history of gestational diabetes. For waist circumference specifically, women measuring more than 35 inches and men measuring more than 40 inches face higher risk.
A simple A1C blood test or fasting glucose test is all it takes. If your result falls in the prediabetic range, you’ll know before any damage becomes harder to reverse.
Prediabetes Can Be Reversed
Unlike many chronic conditions, prediabetes responds remarkably well to lifestyle changes. The landmark Diabetes Prevention Program study found that participants who lost 7% of their body weight (about 14 pounds for someone weighing 200) and exercised 150 minutes per week reduced their risk of developing type 2 diabetes by 58% over three years. For people 60 and older, the results were even more dramatic: a 71% reduction in risk.
That 150 minutes per week breaks down to about 30 minutes of moderate activity, like brisk walking, five days a week. The weight loss threshold is also modest. You don’t need to reach an ideal BMI to see significant metabolic improvement. Losing even 5 to 7% of your body weight can shift your blood sugar back into the normal range and keep it there.
The combination of moving more, eating fewer processed carbohydrates and added sugars, and losing a small amount of weight addresses the root problem: it makes your cells more responsive to insulin again, allowing glucose to enter your cells instead of pooling in your bloodstream. Many people who make these changes see their A1C drop below 5.7% within a year.