Skip to main contentSkip to accessibility services
5 min read
No Ads

Prediabetes: A Warning Sign to Take Seriously

What you can do to stop prediabetes from turning into diabetes.
Tooltip Icon.
Written by
Sam Kelly, MD.
Medically reviewed by
Assistant Professor of Endocrinology - SIU School of Medicine
Last updated April 14, 2021

Prediabetes questionnaire

Use our free symptom checker to find out if you have prediabetes.

What is prediabetes?

Prediabetes means your blood sugar levels are higher than normal, but not high enough to be called diabetes.

Diabetes is when your body does not properly use a hormone called insulin to move sugar (also called glucose) into the cells of your body. This is either because your body does not produce enough insulin or does not respond to insulin properly.

Prediabetes is not in itself dangerous, but it is a warning sign. If you don’t change your diet and exercise routine, prediabetes can lead to type 2 diabetes. Diabetes has serious complications, including heart disease, blindness, kidney failure, peripheral nerve damage, loss of limbs, and stroke.

Most common symptoms

Pro Tip

Two important questions to ask your doctor: What lifestyle changes do I need to make to reverse pre-diabetes? Should I see a diabetes educator to help me with dietary modifications? —Dr. Anis Rehman

Most people with prediabetes do not know they have it. Symptoms of high blood sugar only begin once the levels are high enough to qualify as diabetes.

Having an annual physical, which includes blood tests, is the best way to diagnose it early. These visits are especially important if you have risk factors such as obesity or a family history of diabetes.

Main symptoms

Prediabetes should not cause symptoms. However, some people may have darkened skin in the neck, elbow, armpits, and knees. If you develop diabetes, symptoms include:

  • Increased thirst
  • Increased appetite
  • Increased urination (especially at night)
  • Fatigue
  • Weight loss
  • Blurred vision
  • Sores on the body that do not heal

Causes of prediabetes

Prediabetes occurs when the body has trouble processing the energy (calories) in food, particularly carbohydrates. These carbohydrates are converted into sugars, which travel in the bloodstream. This triggers the pancreas to release the hormone insulin.

Insulin signals tissues throughout the body to take up that sugar to use as energy or to store in fat cells. When insulin doesn’t work right, sugar levels build up in the blood, leading to prediabetes.

In type 1 diabetes the body does not make enough insulin. That is the much rarer form. In type 2 diabetes, the body makes enough insulin but begins to respond to it less. That's known as insulin resistance and it leads to higher levels of sugar in the blood.

High blood sugar levels can cause damage to the heart and blood vessels. It also causes fat to build up in the liver and pancreas where it causes damage and further harms the body’s ability to handle sugar.

Risk factors

Dr. Rx

If making lifestyle changes is challenging, talk to your doctor about metformin to help with improving blood glucose levels. —Dr. Rehman

There are several factors that put you at greater risk of getting prediabetes.

  • Being overweight or obese is the main risk factor. Having a body mass index (BMI) between 25 and 30 means you’re overweight and increases your risk. The risk is even greater when your BMI goes above 30, the definition of obesity.
  • Age (about 45 and older).
  • Lack of exercise.
  • Cigarette smoking.
  • Many medical conditions are thought to increase risk: high blood pressure, high cholesterol, gestational diabetes (diabetes during pregnancy), metabolic syndrome, polycystic ovary syndrome, heart disease, and stroke.
  • Diabetes and prediabetes tend to run in families and are more common in certain racial/ethnic groups. These include African Americans, Alaskan Natives, American Indians, Asian Americans, Hispanic/Latinos, Native Hawaiians, and Pacific Islanders.

Next steps

Make sure you go to your annual checkup with your doctor. If you have any risk factors for diabetes and haven’t been tested recently, see your doctor. A few different blood tests are used to check for prediabetes.

Your blood sugar level can be checked either on an empty stomach (fasting) or after eating. You have prediabetes if:

  • Your fasting blood sugar level is 100-125 mg/dL.
  • Your blood sugar level after eating is 140-199 mg/dL.
  • Your doctor may use a blood test called A1C, a marker of your average blood sugar over the past 2 to 3 months. A1C levels between 5.7% and 6.4% indicate prediabetes.
  • Higher levels of any of these tests mean that you may already have diabetes.

Can prediabetes go away?

Pro Tip

Pre-diabetes is the first sign that you need to make lifestyle changes. It can be reversed before it’s too late and develops into diabetes type 2, which is much harder to reverse. —Dr. Rehman

If you lower your blood sugar levels, prediabetes will go away. You can do that by changing your eating and exercise habits. These steps will also help prevent prediabetes in the first place.

  • Lose weight if you’re overweight. Even losing up to 5% to 10% of your body weight has been shown to reverse pre-diabetes.
  • Eliminate processed foods with lots of added sugar. It is helpful to look at food labels to see how much added sugar foods have.
  • Eat healthy food like fruits, vegetables, fish, chicken, beans, and nuts.
  • Avoid saturated fats in foods like fried foods, animal products like bacon, processed deli meats, and red meat like beef.
  • Get at least 150 minutes of moderate exercise a week. Some examples include dancing, swimming, bicycling or spinning, playing sports, brisk walking, and aerobics classes.
  • Quit smoking if you smoke.
  • If you have blood pressure or high cholesterol, make sure these are under control by taking any prescribed medicines and following up with your doctor. If uncontrolled, the combination of these conditions with prediabetes increases your risk of heart disease and stroke.

With these lifestyle changes, you will lower your chance of developing type 2 diabetes. If prediabetes does progress to diabetes, you will likely have to start taking medications for the diabetes.

Children and prediabetes

Traditionally prediabetes and type 2 diabetes were thought to occur just in adults. But with increasing rates of obesity, prediabetes and type 2 diabetes are becoming more common among children and teenagers.

If your child suddenly has symptoms of diabetes such as frequent urination, increased thirst and hunger, weight loss, fatigue, or blurred vision, see your pediatrician right away. This might mean they have type 1 diabetes, which can be fatal if not treated.

Type 1 diabetes progresses rapidly and so it is not caught at the prediabetes stage. Type 2 diabetes usually comes on gradually so there is time to catch it before it becomes serious.

Children and teens need to follow the same advice for exercise, calorie control, and weight loss.

Follow up

If you have risk factors for prediabetes or have been diagnosed with it, follow up with your doctor at least once a year to get routine blood tests. Check your blood sugar at home once every few weeks and keep a log of your blood levels to review with your doctor.

Share your story

Dr. Kelly is a graduate of the University of Pennsylvania Perelman School of Medicine, specializing in internal medicine and bioethics. He received his undergraduate degree from Emory University with a BA in Spanish. Dr. Kelly has formal training in medical interpretation and translation, along with several years of professional experience in medical communication and editing work for publication.

Was this article helpful?

Tooltip Icon.
Read this next