Diabetes Forecast

How to Prevent and Treat Prediabetes

By Stacy Lu , ,

Zinkevych/Thinkstock (woman); Wand_Prapan/Thinkstock (apple); psphotograph/Thinkstock (pen)

Do you have prediabetes? Are you sure? About one-third of adults over the age of 18 have the condition, according to the Centers for Disease Control and Prevention (CDC). And about 90 percent of those people don’t know they have it.

There’s good news, though. If you’re aware of your prediabetes, you can prevent it from progressing, and can even reverse it. Here’s what you need to know in order to stay healthy.

The Development

When you eat foods containing carbohydrates, your digestive system breaks them down into glucose that enters your bloodstream. If your body is working as it should, beta cells in the pancreas produce insulin, a hormone that helps cells absorb the glucose and use it for energy. As the cells drink up the glucose, blood glucose levels fall.

Sometimes, though, the cells don’t properly respond to insulin—a condition called insulin resistance—and the body has to produce extra insulin in order for the cells to absorb glucose.

Over time, the pancreas becomes unable to keep up with the increased demand for insulin, and excess glucose builds up in the bloodstream. The result: prediabetes or type 2 diabetes, depending on how high blood glucose is compared to normal (see “Testing for Prediabetes,” below).

 The Risk Factors

The biggest risk factors for prediabetes are a body mass index (BMI, a ratio of weight to height used to estimate how close a person is to a healthy weight) over 25, being over 45 years old, and having an immediate relative with type 2 diabetes. “Every one of us has a Venn diagram where age, genetics, and body weight converge to lead to diabetes,” says Leigh Perreault, MD, associate professor of medicine at the University of Colorado in Aurora, Colorado. People who exercise fewer than three times per week, those who carry extra weight around the abdomen, and women who’ve had gestational diabetes are also more likely to develop prediabetes. The American Diabetes Association has an online quiz that can help you determine if you’re at risk.

The Diagnosis

Because there are no symptoms of prediabetes, you may have it without realizing it. That’s why it’s important to know your risk and ask your doctor about blood tests. Prediabetes is diagnosed when one or more screening tests (see “Testing for Prediabetes,” above) find blood glucose levels that are higher than normal but lower than those seen with type 2 diabetes.

There are two types of prediabetes, based on when blood glucose is elevated. If a fasting plasma glucose (FPG) test, which measures blood glucose after at least eight hours of fasting, determines your levels are higher than normal (over 99 mg/dl) but below the threshold for diabetes (126 mg/dl or above), you have impaired fasting glucose. In this case, the liver is resistant to insulin and makes too much glucose during fasting.

But if, during an oral glucose tolerance test (OGTT), your blood glucose is elevated two hours after drinking a sweet drink, you have impaired glucose tolerance. This is present when muscle tissue, which is stimulated by insulin to take in glucose from food, is resistant to insulin, causing blood glucose levels to be high after meals.

If you’ve had abnormal results from any of the three diabetes tests (A1C, fasting plasma glucose, or oral glucose tolerance test), your doctor will likely recommend that you be retested within three to six months and every year thereafter to make sure you haven’t progressed to type 2 diabetes. “Having a historical record is important. I look at blood sugar levels over time for each patient,” says Adrian Vella, MD, professor of medicine in the Division of Endocrinology at the Mayo Clinic in Rochester, Minnesota.

The Treatment

So, you’ve been diagnosed with prediabetes. Here’s some good news: Research shows that lifestyle changes can return blood glucose levels to a normal range and prevent progression to type 2 diabetes. A weight loss of 5 to 7 percent and 150 minutes of moderate exercise per week can reduce the chance of a person with prediabetes developing type 2 diabetes by 58 percent, says Mark Schutta, MD, medical director of the Penn Rodebaugh Diabetes Center in Philadelphia. “I tell my patients, ‘You can treat this into remission. It’s attainable for most people with prediabetes.’ ”

Weight loss is critical to attaining healthy blood glucose levels. “We start by helping people find out where their empty calories are—things like fruit juices, soda, and processed foods,” Schutta says.

He also counsels people to build exercise into their daily routines because exercise uses glucose for fuel and makes cells more sensitive to insulin. “People are not moving like they did 50 years ago, and it’s a big problem,” Schutta says. To increase your daily physical activity, first count the number of steps you take each day using a pedometer, fitness tracker such as Fitbit, or smartphone fitness-tracking app. Under a doctor’s supervision, try to increase your step count with exercise and/or extra movement, such as taking the stairs or parking your car far away from a store entrance.

For more guidance, ask your doctor for a referral to the National Diabetes Prevention Program, a yearlong, CDC-endorsed program in which lifestyle coaches guide participants through eating healthier, getting active, and managing stress. The program may be covered by insurance or your employer’s wellness plan. Learn more, and find a program near you.

Depending on your risk factors, your doctor may also prescribe an oral diabetes medication (metformin is most common) to help reduce blood glucose levels. While diabetes drugs can work, they’re less effective than lifestyle improvements. Schutta says he’s most likely to prescribe medication to patients who have a higher likelihood of progressing to type 2 diabetes or have cardiovascular risk factors such as hypertension and high cholesterol.

Weight-loss surgery may be an option for people with a BMI over 40, or those with a BMI over 35 and health issues such as hypertension, Perreault says.

The Long Term

There’s a reason doctors don’t talk about “curing” prediabetes: Even if you’ve returned to normal blood glucose levels, you’ll need to commit to a healthy lifestyle to stay on track, including maintenance of weight loss, and have your blood glucose checked at least every three years. Should you stop managing your prediabetes (by gaining weight, for example) the high blood glucose will likely return. Over time, you’ll be at greater risk for other conditions, such as cardiovascular disease—and, of course, for type 2 diabetes.

“Once you’ve had prediabetes, you know where your tipping point is. You need to stay on top of things, especially as aging becomes a bigger factor,” Perreault says. “I tell my patients, ‘This isn’t just about losing weight once. We’re in it for the long haul.’ ”

Testing, Testing

When should you be tested for prediabetes? According to the 2018 Standards of Medical Care in Diabetes, a health care professional will check for prediabetes in overweight or obese adults who:

  • Have a first-degree relative (mother, father, sister, or brother) with diabetes

  • Are African American, Latino, American Indian, Asian American, or Pacific Islander

  • Have a history of cardiovascular disease

  • Have high blood pressure
  • Have an HDL (“good”) cholesterol level less than 35 mg/dl and/or a triglyceride level greater than 250 mg/dl
  • Have polycystic ovary syndrome

  • Are physically inactive
  • Have other clinical conditions associated with insulin resistance


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