Borderline diabetes is another name for prediabetes, a condition that makes it more likely that you’ll develop type 2 diabetes. People with borderline diabetes have some insulin resistance, but their blood sugar levels are not high enough for a diabetes diagnosis.

Some people use the term “borderline diabetes” to refer to prediabetes. Prediabetes is a term used by medical professionals and is a condition that may occur before a person develops type 2 diabetes.

Also known as impaired fasting glucose or glucose intolerance, prediabetes occurs when your blood sugar levels are higher than normal, but they’re not quite high enough to be considered a sign of diabetes.

During the prediabetes phase, your pancreas still produces enough insulin in response to ingested carbohydrates. But the insulin is less effective at removing the sugar from the bloodstream, so your blood sugar remains high. This condition is called insulin resistance.

If you have prediabetes, you should know you’re not alone. In 2019, it was estimated that 96 million adults in the United States were diagnosed with prediabetes, which translates to around 1 in 3 adults.

Having prediabetes doesn’t mean you’ll definitely develop diabetes. But it’s important to make changes to your diet and lifestyle to prevent the condition from progressing.

In fact, it’s estimated that between 15% to 30% of people with prediabetes will develop diabetes within the next 3-5 years if no lifestyle changes are made.

Someone with insulin resistance in its early stages can develop type 2 diabetes if it continues long enough.

But prediabetes doesn’t usually cause any symptoms and only 20% of people with prediabetes even know they have it.

Any of these risk factors can increase your chances of developing prediabetes:

  • having overweight or obesity
  • being physically inactive
  • being age 45 or older
  • having high blood pressure or high cholesterol levels
  • having a close family member with type 2 diabetes
  • having a history of heart disease, stroke, gestational diabetes, or polycystic ovary syndrome

Prediabetes is a silent condition, so getting a regular wellness checkup is important for early detection. If you think you might have borderline diabetes, it’s best to discuss your concerns with a doctor.

If a doctor suspects you may have prediabetes, they’ll most likely perform a hemoglobin A1c (HbA1c) test or oral glucose tolerance test (OGTT).

HbA1c is an indicator of your blood sugar control over the past 3 months, so it’s often a better overall picture than a single fasting blood sugar check. An HbA1c level between 5.7 and 6.4 indicates prediabetes.

High blood glucose levels, especially if they’re left untreated, can affect other systems in your body. This can leave you vulnerable to a variety of health risks and chronic health conditions. For example, uncontrolled diabetes can lead to:

The high insulin levels that come with insulin resistance can cause additional problems.

A large, multicenter research study called the Diabetes Prevention Program looked into how lifestyle changes could help prevent diabetes. What they found should give people at risk of diabetes a lot of hope.

With modest weight loss and exercise, study participants reduced their risk of developing diabetes by 58% over 3 years.

Therefore, making changes to your diet and lifestyle can be especially beneficial for those with prediabetes and may help support blood sugar control and overall health.

Balanced diet

Focus on nutrient-dense foods like fruits, vegetables, lean proteins, and heart-healthy fats. When choosing grains, be sure to choose complex carbohydrates, like whole grains.

You should also aim to limit your intake of added sugars, like those in processed baked goods or sugar-sweetened beverages. Foods high in added sugar can raise blood sugar levels and are also often lacking in important nutrients.

For help in planning meals to prevent diabetes, consider scheduling an appointment with a dietitian. The American Diabetes Association also offers simple tips for diabetes-friendly cooking.

Physical activity

Aim for 150 minutes of exercise each week, or around 30 minutes of exercise for 5 days per week.

This can include a variety of activities, including walking, biking, swimming, hiking, or dancing.

Maintain a moderate weight

Though you can develop prediabetes at any size, having overweight or obesity can increase the risk.

Talk with a doctor or dietitian about whether making changes to your diet or exercise routine may be beneficial to help you reach or maintain a moderate weight and reduce your risk of developing diabetes.


If you do have prediabetes, a doctor may prescribe a medication, like metformin (Glumetza, Glucophage, Fortamet, Riomet). This can also help increase insulin sensitivity and keep blood glucose levels in check.

Talk with your doctor before starting any diet or lifestyle changes. It’ll give you the best chance of preventing diabetes in the first place while also avoiding any potential complications from uncontrolled diabetes.

Keep in mind that being diagnosed with prediabetes doesn’t have to mean you’ll develop diabetes.

In fact, making moderate adjustments to your diet and lifestyle can help prevent prediabetes from progressing while also improving your overall health.