What Does Prediabetes Really Mean?

It’s generally accepted that prediabetes is a condition in which blood sugar levels are higher than normal, but not yet in the diabetes range. According to the Centers for Disease Control and Prevention, approximately 86 million American adults have prediabetes, and many don’t know it. Receiving the prediabetes diagnosis can be a wake-up call that helps people make lifestyle changes to help prevent or delay the onset of type 2 diabetes. But there’s debate over the usefulness of the term “prediabetes.”

According to the American Diabetes Association (ADA) the following lab values indicate prediabetes:

• An A1C of 5.7 to 6.4 percent
• A fasting blood glucose (FBG) of 100 mg/dL to 125 mg/dL
• An oral glucose tolerance test (OGTT) of 140 mg/dL to 199 mg/dL

Prediabetes may also be referred to as impaired fasting glucose or impaired glucose tolerance, depending on the test that was used to diagnose the condition.

Having prediabetes doesn’t guarantee that you’ll develop diabetes, and there are steps you can take to bring your blood sugar levels back to the normal range. According to the ADA, losing 7 percent of your body weight and exercising for 30 minutes a day, five days a week, can lower your risk of developing type 2 diabetes by 58 percent. But some experts feel that the term “prediabetes” isn’t strong enough to encourage people to make these types of lifestyle changes.

The Great Debate

The “pre” in prediabetes can make it seem like a separate, harmless condition—it’s not diabetes. But, in fact, prediabetes may not be completely harmless—the long-term damage associated with diabetes may have already started. A review published in November 2016 in BMJ found that prediabetes is associated with an increased risk of cardiovascular disease, even when the lowest thresholds (an A1C of 5.7 percent, for example) were used to diagnose prediabetes. Diabetes advocate Riva Greenberg has suggested changing the name “prediabetes” to “stage 1 diabetes” to highlight the seriousness of the condition and motivate more people to make the necessary changes to prevent it from progressing to diabetes.

But not everyone agrees. Some people argue that prediabetes is too broad of a term and can cause people to worry about, and even take medication for, a condition that may never turn into diabetes at all.

The ADA has a lower threshold for diagnosing prediabetes than most other organizations. In fact, not all organizations even use the label “prediabetes.” The World Health Organization (WHO) recommends not using the term in order “to avoid any stigma associated with diabetes and the fact the many people do not progress to diabetes as the term applies.” It uses the term “intermediate hyperglycemia” to describe blood sugar levels that fall between the normal range and the diabetes range instead. Intermediate hyperglycemia is defined as an impaired glucose tolerance of 140 to 200 mg/dL and a fasting blood glucose (FBG) of 110 to 125 mg/dL, slightly higher than the ADA criteria.

The ADA has lowered its threshold over the years, most recently in 2010 when it changed the A1C criteria for diagnosing prediabetes from 6.0 to 5.7 percent. This lower diagnostic threshold broadens the definition of prediabetes, meaning that more people can be diagnosed with the condition, even those with a minimal risk of developing diabetes. According to WHO, lowering the diagnostic threshold can needlessly increase the prevalence of prediabetes. If China adopted the ADA guidelines, for instance, nearly 493 million people would be diagnosed with prediabetes, according to one analysis.

The logic behind creating the category “prediabetes” is to identify those people who will go on to develop diabetes so that steps can be taken to prevent it. But just how well does prediabetes predict who will progress to diabetes? According to that same analysis, of 100 people diagnosed with prediabetes, less than half will develop diabetes within ten years. For those who don’t, the downsides of being diagnosed with prediabetes include the need for medical care and treatment, which comes with its own set of risks and costs; challenges with insurance and employment; anxiety about future complications; and issues with self-image.

The Medication Question

Some people with prediabetes may be started on drugs to prevent or delay diabetes. These are the same drugs used to treat diabetes, however, and the benefit of starting these before you develop diabetes is not known. But studies have shown that lifestyle interventions—eating a healthy diet, getting regular exercise, and maintaining a healthy weight—can help delay or prevent diabetes and the onset of complications. These are the same healthy habits that are good for everyone. So the question becomes—is there any value in using the label “prediabetes” for a certain group of people, when the entire population would benefit from the same advice?

Lifestyle Changes for Prediabetes

However prediabetes is defined, the first line of treatment is making healthy lifestyle changes to help bring your blood sugar back to normal. Try the following tips:

• Eat a healthy, low carb, low glycemic diet. Focus on whole, low-carb fruits and vegetables and unprocessed proteins like dairy, meat, and fish.
• Watch your portion sizes. You can still eat many of the foods you enjoy, just in smaller amounts.
• Skip sugary drinks. Drink water instead of juice, soda, or sweet, coffee drinks.
• Get moving. Aim to get at least 30 minutes of moderate exercise on most days of the week. You don’t need to get all 30 minutes at once—breaking it into three 10-minute blocks of activity is just as good for you.
• Don’t smoke. Or quit if you do. Smoking can make blood sugar harder to control.
• Try stress management techniques. Stress can wreak havoc on blood sugar. Try yoga, meditation, or deep breathing exercises.

Created March 2017.