Prediabetes: What Does It Mean?

Prediabetes – where blood sugar levels are high, but not high enough for a diagnosis of type 2 diabetes –is not something you should dismiss.

Prediabetes can have long-term effects, including damage to blood vessels, heart and kidneys, increasing your risk of type 2 diabetes, heart attack and stroke. However, it is possible to halt the progression of prediabetes so that it doesn't become type 2 diabetes.

Matthew J Lash, MD, family medicine physician with Franciscan Physician Network Greenwood Parke Family Medicine, discusses the risks, causes and symptoms of prediabetes, as well as ways to improve your diet and lifestyle.

Key Takeaways: Prediabetes

• Prediabetes develops when blood sugar levels are higher than normal but not high enough for a diabetes diagnosis, and it is an important warning sign that should not be ignored.
• Many people with prediabetes have no noticeable symptoms, which is why regular screening is essential for people 35 and older or with risk factors like excess weight or family history.
• Prediabetes significantly increases the risk of developing type 2 diabetes as well as heart disease, stroke, and damage to organs such as the kidneys and eyes.
• Lifestyle changes such as modest weight loss, regular physical activity, and healthier eating habits can slow, prevent, or even reverse the progression from prediabetes to type 2 diabetes.

What Is Prediabetes?

According to the CDC, prediabetes is caused by the cells in your body not responding normally to insulin. Insulin is a hormone made by your pancreas that acts like a key, letting blood sugar into cells for use as energy.

In prediabetes, your cells develop insulin resistance, making it difficult for insulin to transport glucose into your cells. This triggers your pancreas to produce even more insulin, trying to get cells to respond. Eventually, your pancreas can’t keep up, and your blood sugar rises, setting the stage for prediabetes—and type 2 diabetes down the road.

“Your blood sugar is elevated, but it's not elevated to the extent of what we would categorize as diabetes. But it's certainly not normal either,” Dr. Lash said.

What Does Prediabetic Mean?

Without enough insulin, extra glucose stays in your bloodstream rather than entering your cells. 

People with prediabetes have up to a 40 percent chance of developing diabetes over the next 12 years, according to the a 2023 JAMA Review.  But your risks go beyond type 2 diabetes.

Other long-term effects of prediabetes may include damage to blood vessels, heart, kidneys and eyes. It also increases your risk of heart attack and stroke.

However, it is possible to halt the progression of prediabetes.

How Common Is Prediabetes?

More than one-third of Americans 18 or older (88 million) have prediabetes, according to the U.S. National Institutes of Health. Nearly 29 million of them are under 45 years old.

What Are Symptoms Of Prediabetes?

Prediabetes can be difficult to recognize. Of the 88 million Americans with prediabetes, more than 84% don’t know they have it. People usually find out that they have the condition after being tested for diabetes. This is in part because prediabetes often doesn't have symptoms.

The National Institute of Diabetes and Digestive and Kidney Diseases says some less typical symptoms of prediabetes include:

• Darker skin on the back and sides of the neck or near the armpits
• Growth of new skin tags
• Changes in how the eye works due to damaged blood vessels (retinopathy)

Am I At Risk For Prediabetes?

The risk factors for prediabetes are generally the same as the risk factors for developing diabetes.

"Some risk factors for prediabetes are modifiable, while some are not modifiable," Dr. Lash said.

While scientists don’t know the exact causes of prediabetes, excess weight and lack of exercise are two of the leading risk factors.

Your weight

“One would be, being overweight and that doesn't mean necessarily obesity, that just means being overweight. If your BMI is over 25 and above that's a risk factor,” Dr. Lash said. “You’re at an even higher risk factor if you have a lot more belly weight.”

Your health history

Other risk factors for prediabetes include:

• High cholesterol
• High blood pressure
• A family history of diabetes
• A personal history of gestational diabetes (diabetes only during a pregnancy)
• Having given birth to a baby that weighed more than 9 pounds
• Having polycystic ovary syndrome (PCOS), also known as PMOS

Your age

“As you get older, your pancreas gets older too. It doesn't make as many insulin-producing cells that will release this insulin. It has more trouble fighting insulin resistance,” said Dr. Lash. “So, as you age, and the ADA would say over the age of 35, you're at higher risk, regardless of other risk factors.” Though after 70 this risk declines.

Your ethnicity

Black, Hispanic, Native American and Asian Americans experience higher rates of prediabetes than white Americans. Though progression from prediabetes to diabetes remains the same for all groups.

Lifestyle choices

• Consuming a diet high in sugary foods and red or processed meats
• Smoking
• Not getting enough exercise.

The reality is, at some point, your doctor may say it's time to be screened for prediabetes.

“Everyone is at risk. About 34% of the United States right now has prediabetes,” said Dr. Lash. “And if you look at the criteria with all the risk factors and when you should screen, at some point in someone's life, they're probably going to meet enough of those risk factors to be screened.”

Should I Be Screened For Prediabetes?

The American Diabetes Association says if you're over 35 years old without any other risk factors for diabetes that you should be screened for prediabetes.

“Everyone at some point in life should be screened for prediabetes,” said Dr. Lash.

As the risk of diabetes grows, so does the need for testing. If you're older than 35 and overweight, "considering" such a test isn't enough. If you haven't already had the fasting plasma glucose test, make an appointment. Generally, you're considered to have diabetes if your A1C on two separate tests is 6.5 or higher, or if your glucose reading after fasting -- confirmed by a second test -- is 126 or higher, or if you have a level of more than 200 plus symptoms of high blood sugar.

According to the American Diabetes Association, the test is also a good idea for anyone under 35 who is overweight and has another risk factor for diabetes or heart disease. If the test results come back normal, you can wait up to three years before being retested -- unless your doctor recommends testing more frequently due to an increased risk of diabetes.

How Do I Get Tested For Prediabetes?

It’s important to know the types of tests available for prediabetes.

“There are many tests you can do,” said Dr. Lash. “One is called a fasting blood sugar test, which means the night before you get your labs you don't eat and you can only have water after dinner. That's going to show what your blood sugar is when you haven't had a meal. If it's 100 or higher, that would indicate a level that is in the prediabetes range which indicated impaired fasting glucose, but you should then get a confirmatory test.”

“Another very common test that is a common screener and the next step for those with impaired fasting glucose is called a hemoglobin A1C or HbA1c. This is looking at is your average blood sugar over typically the last three months.” Though that can be limitations in this screening for certain red blood cell diseases.

An A1C reading between 5.7% and 6.4% is considered prediabetes. A higher A1C reading could indicate diabetes.

The next form of confirmatory testing is called an oral glucose tolerance test. This test starts like the fasting test with fasting for about 12 hours then going to the lab to get an initial fasting test. Then they give you a super sugary drink and measure your sugar over a couple hours. This test is typically done from women who are pregnant and, on the verge, but can be done when there is a concern, but is more involved due to the length of testing.

A final test that may be obtained is a fasting insulin test. This can be done when there is a concern with the skin or other findings and the fasting glucose is normal. This would indicate high insulin levels but your sugar is normal with fasting. These are more controversial, and currently used mostly for research, though some provider find them helpful in a full picture.

Can I Prevent Prediabetes?

There are ways to help prevent prediabetes. Studies show at least 150 minutes a week of moderate physical activity (such as walking or jogging) and a diet that's low in fat and rich in produce and whole grains can help prevent or delay diabetes. If you're overweight, losing just 7 percent to 10 percent of your body weight can make a big difference.

“Once you convert to diabetes, almost every organ you can think about could be damaged by diabetes, so it is really important to try to prevent that,” said Dr. Lash. “Even if you're thinking you're living a very healthy life, but you realize you have some of the risk factors, checking with your doctor and seeing if screening for diabetes would be appropriate for you. Also, you can reverse the pathologic processes of metabolic syndrome and insulin resistance, by exercising, portion sizing, dieting and if overweight, trying to lose 7% of your body weight.”

According to the CDC, a small amount of weight loss means around 7% to 10% of your body weight, which is 14 to 20 pounds for a 200-pound person. Regular physical activity means getting at least 150 minutes a week of brisk walking or a similar activity. That’s just 30 minutes a day, five days a week.

How Do I Treat Prediabetes?

Learning how to reverse prediabetes through healthier diet and lifestyle choices is one of the main treatment strategies recommended by the NIDDK.

A study of more 1,000 people published in the journal JAMA Internal Medicine revealed that even “modest” lifestyle changes, including losing 4.5 to 6.5 pounds and increasing exercise, reduced the risk of developing diabetes by 40% to 47% over a 2 year period.

The NIDDK also notes that your doctor may prescribe a medicine called metformin or other meds for your prediabetes to help delay the onset of diabetes.

Can You Reverse Prediabetes?

The good news? If you have a prediabetes diagnosis, lifestyle changes may enable you to reverse prediabetes. Learn more about the steps to help reverse prediabetes.

If you need additional support, Franciscan Health offers a Diabetes Prevention Program to help you invest in your long-term health and help prevent diabetes.