Updated on March 25, 2024.
When was the last time you had your blood sugar checked? Even if you feel healthy, skipping regular screenings could affect your health if you have high blood sugar and don't know it. In fact, about 20 percent of the 37 million people in the United States with diabetes are not diagnosed, according to the Centers for Disease Control and Prevention (CDC).
It’s a similar situation for those with prediabetes, a condition with higher-than-normal blood sugar that often leads to type 2 diabetes. The CDC estimates that about 80 percent of the 96 million U.S. adults with prediabetes aren’t aware of it.
By testing and monitoring your blood sugar, you may be able to take action to prevent the development of type 2 diabetes and treat the condition properly if you’re diagnosed.
Factors that affect screening frequency
Blood sugar tends to rise with age. So, healthcare providers (HCPs) generally recommend testing every three years, starting at age 45. If you are overweight or obese and have one of the diabetes risk factors below, you should be tested earlier and more often: every one to three years.
- Sedentary lifestyle: Regularly sitting for long periods of time increases your risk for diabetes
- Family history of diabetes: If you have a sibling or parent with diabetes, you are at greater risk.
- Certain racial and ethnic backgrounds: Compared with other groups, African American, Alaska Native, Native American, Latino, Pacific Islander, and Asian American people have higher odds of diabetes.
- History of specific health problems: If your blood pressure is high (at or above 140/90 mm Hg), you have unhealthy cholesterol levels, you have heart disease, or you've previously tested positive for high blood sugar, you're at increased risk of developing diabetes. A history of gestational diabetes (which happens during pregnancy) or polycystic ovary syndrome (PCOS, a hormonal condition that causes many small growths in the ovaries) raises your chances, as well.
Be aware of symptoms that might indicate diabetes. If you notice more frequent urination, hunger, thirst, or fatigue—or if you experience sudden, unexplained weight loss or vision changes—reach out to an HCP immediately to schedule a blood sugar test. Many people don’t experience any symptoms, however, so be sure to get tested if you have risk factors.
Blood sugar tests
An HCP may recommend one or more tests, depending on your personal diabetes risk factors; certain tests will likely be followed up with additional tests. How you prepare for each screening will depend on your test, so be sure to follow your HCP’s instructions. Typical test options include:
- A1C blood test: This test measures your average blood sugar levels over the prior three months. An A1C between 5.7 and 6.4 percent indicates prediabetes, while 6.5 percent or higher indicates diabetes.
- Fasting blood sugar test: This measures your blood sugar level in the morning after not eating all night. A level between 100 and 125 mg/dL indicates prediabetes, while 126 mg/dL or higher indicates diabetes.
- Glucose tolerance test: This measures your blood sugar level after a night of fasting. You’ll be tested at least twice, however—once before you drink a glucose liquid, and then again from one to three hours afterward. After two hours, a level between 140 and 199 mg/dL indicates prediabetes, while 200 mg/dL or higher indicates diabetes.
- Random blood sugar test: This measures your blood sugar levels at the time of the test. You can take it anytime, without fasting beforehand. A level of 200 mg/dL or above may indicate diabetes if you also display typical symptoms such as thirst, frequent urination, or blurry vision.
Once you’ve been tested, it’s important that an HCP thoroughly explains the meaning of your results. Be sure to ask questions if any part of the explanation is unclear. Taking notes at the appointment or having someone with you may help you remember information, as well.
Changes to make moving forward
If you test positive for prediabetes, you are at higher risk for developing type 2 diabetes. But it does not necessarily mean that you will definitely develop this chronic condition. Lifestyle changes can make a difference in preventing the development of type 2 diabetes, including eating a healthy diet rich in fruits, vegetables, whole grains and lean proteins and low in added sugar, salt and saturated fat (which is solid at room temperature, like butter), quitting tobacco, getting regular physical activity as you are able.
And if your test indicates type 2 diabetes, these lifestyle changes—along with medications—can help you manage the condition and avoid complications.
