You feel fine. You’re going to work, taking walks, playing with the grandchildren, traveling, and doing everything you normally do.
Then you have your yearly blood work.
Your doctor looks at the results and says: “Your blood sugar is a little high. You have prediabetes.”
Wait a minute. Prediabetes? How can you have a problem with your blood sugar when you don’t feel any different?
That’s one of the most important things to understand about prediabetes.
Most people don’t feel it.
There will be no pain. No dizziness. No obvious change in energy. Nothing that tells you your blood sugar has slowly been moving in the wrong direction.
But that laboratory result is giving you valuable information.
And here’s the other thing I want you to understand: Prediabetes does not mean diabetes is inevitable. Think of it as an early warning sign—and an opportunity to make changes while there is still time.
What Exactly Is Prediabetes?
Your body uses a type of sugar called glucose for energy.
After you eat, glucose enters your bloodstream. Your pancreas releases insulin, which helps move glucose from your blood into your cells.
As we discussed in our last article, sometimes the body’s cells become less responsive to insulin. We call this insulin resistance.
Your pancreas initially compensates by producing more insulin. Eventually, however, blood glucose may begin to rise.
When blood glucose is higher than normal but not yet high enough to meet the criteria for diabetes, we call it prediabetes.
Prediabetes is common. The CDC estimates that more than 115 million American adults have prediabetes. Even more striking, about 8 out of 10 don’t know they have it.
That makes sense when you realize how few symptoms it usually causes.
How Do We Find Prediabetes?
We usually find it with a blood test. Two of the most common tests are the fasting blood glucose and A1C.
Let’s make both easy to understand.
Fasting Blood Glucose: A Snapshot
A fasting glucose test measures the amount of glucose in your bloodstream at one particular moment. Usually, you haven’t eaten or had anything containing calories for at least eight hours before the test.
Think of this test as a photograph of your blood sugar.
For most nonpregnant adults:
- Normal: less than 100 mg/dL
- Prediabetes: 100–125 mg/dL
- Diabetes: 126 mg/dL or higher
A result in the diabetes range generally needs to be confirmed with repeat testing unless there are clear symptoms of diabetes or another test confirms the diagnosis.
But remember the important word here:
Snapshot. Your fasting glucose tells us what your blood sugar was doing at that particular time.
That’s useful, but it doesn’t tell the whole story.
That’s where A1C comes in.
A1C: The Bigger Picture
A1C is another blood test, but it gives us different information.
Glucose in your bloodstream attaches to hemoglobin, a protein found inside your red blood cells. The A1C test measures the percentage of hemoglobin that has glucose attached to it.
Because red blood cells live for roughly three months, your A1C gives us an estimate of your average blood glucose over the previous two to three months, with more recent weeks contributing more to the result.
Think of fasting glucose as one photograph. Think of A1C as a short video.
For most nonpregnant adults:
- Normal: below 5.7%
- Prediabetes: 5.7%–6.4%
- Diabetes: 6.5% or higher
Again, a result suggesting diabetes is usually confirmed with another test when there are no classic symptoms.
A1C has another advantage: you generally don’t have to fast before having it checked.
One Test Doesn’t Always Tell the Whole Story
Here’s something that sometimes surprises people. Your fasting glucose might be normal while your A1C is in the prediabetes range. Or the opposite can happen.
That’s because these tests measure different aspects of your blood sugar.
There are also situations where A1C may be less reliable. Certain types of anemia, kidney or liver disease, blood loss, blood transfusions, pregnancy, and some hemoglobin variants can affect the result.
Your doctor can decide which test—or combination of tests—makes the most sense for you.
The important thing is not to become obsessed with one number. We look at the bigger picture.
“But I Feel Fine!”
I heard this many times during my years in practice. And the patient was usually right. They did feel fine.
Prediabetes usually doesn’t cause noticeable symptoms. That’s exactly why screening matters.
You don’t want to wait until excessive thirst, frequent urination, unexplained weight loss, blurry vision, or other symptoms of significant high blood sugar appear before discovering there’s a problem.
Prediabetes gives you an earlier warning. That’s valuable information.
Prediabetes Is Not a One-Way Street
This may be the most important part of today’s article.
If your doctor tells you that you have prediabetes, I don’t want you walking out of the office thinking: “Well, I guess I’m going to get diabetes.”
That’s simply not what the diagnosis means.
Prediabetes increases your risk of developing type 2 diabetes, but progression is not inevitable.
One of the strongest examples comes from the landmark Diabetes Prevention Program.
Researchers studied adults at high risk for developing type 2 diabetes. Participants in the intensive lifestyle program aimed for at least 150 minutes of physical activity each week and about 7% weight loss.
Over roughly three years, the lifestyle program reduced the development of type 2 diabetes by 58% compared with placebo.
Among participants age 60 and older, the reduction was even greater—71%. Read that again. People in their 60s and older were able to substantially change their risk.
That’s an important message for anyone who thinks, “I’m too old for lifestyle changes to make a difference.” You’re not.
What Can You Do?
You don’t need to overhaul your entire life tomorrow. Start with the big things that consistently matter.
Move more. Walking, cycling, swimming, resistance exercise, and other physical activities help your muscles use glucose.
Build and maintain muscle. Muscle is an important place for glucose disposal. Strength training becomes particularly valuable as we age.
Improve the quality of your diet. Build meals around vegetables, fruits, beans, whole grains, lean protein, and other minimally processed foods while limiting highly refined carbohydrates and sugary drinks.
Lose some weight if you need to. You don’t necessarily need dramatic weight loss. Even modest weight loss can improve insulin sensitivity and reduce diabetes risk in people carrying excess weight.
Get enough sleep. Poor sleep can interfere with normal glucose regulation.
And don’t underestimate small changes. A 10-minute walk after dinner. Strength training twice a week. Replacing a sugary drink with water. Adding vegetables to lunch. Going to bed 30 minutes earlier. Small habits repeated hundreds of times become meaningful changes.
Dr. Mike’s Take
I don’t like thinking of prediabetes as a disease waiting to happen. I prefer to think of it as your body tapping you on the shoulder. It’s saying: “Pay attention. Something is starting to change.” That’s useful information.
You have discovered a problem before it has necessarily become a bigger problem.
And if you’re 55, 65, 75, or even older, don’t assume it’s too late to improve your health. The research tells us otherwise.
Bottom Line
Prediabetes means your blood glucose is higher than normal but hasn’t reached the diabetes range. And you probably won’t feel it.
That’s why knowing your fasting glucose and A1C can be so valuable.
If your numbers are creeping upward, don’t panic—and don’t ignore them. Ask what you can do next. Move more. Maintain your muscle. Improve your diet. Work toward a healthier body composition if needed. Get adequate sleep. And keep checking your numbers.
Remember this: Prediabetes is a warning sign, not a guarantee of what happens next.
What you do after receiving that warning can make a real difference.
This article is for educational purposes and is not a substitute for individualized medical advice. Talk with your healthcare professional about appropriate diabetes screening and what your results mean for you.PR