By Jenilee Matz, MPH
Diabetes is on the rise. Close to 26 million Americans have diabetes, and 7 million of them don’t even know they have it yet. What’s more, nearly 80 million people are considered to have prediabetes.
Don’t let these numbers alarm you too much, though. Instead, focus on the numbers you can control. Your blood sugar levels and other numbers can reveal a lot about your health. Knowing these numbers is the first step to taking charge of your diabetes. And keeping them in check can help reduce your risk for dangerous complications, like heart attack, blindness and infections.
Numbers for Diabetes Diagnosis
If your doctor suspects you have diabetes, you’ll likely have a hemoglobin A1C (glycated hemoglobin), an oral glucose tolerance test (OGTT) or a fasting plasma glucose (FPG) test. The FPG test measures your blood glucose (blood sugar) after not eating for at least eight hours. The test can determine if you have diabetes or prediabetes.
FPG test results:
- Normal blood sugar: Below 100 mg/dL
- Prediabetes: Between 100 and 126 mg/dL
- Diabetes: Higher than 126 mg/dL
If your FPG test comes back in the diabetic range, your doctor may diagnose you with diabetes. Or he or she may send you for an oral glucose tolerance test (OGTT) before making a diagnosis. The OGTT is also used to check those who have an FPG test that comes back in the prediabetes range. This test measures your blood sugar levels at different intervals after you drink a sweet beverage.
- Normal blood sugar: Below 140 mg/dL two hours after drinking beverage
- Prediabetes: 140 to 199 mg/dL two hours after drinking beverage
- Diabetes: 200 mg/dL or higher two hours after drinking beverage
Your Must-Know Numbers
If you have diabetes, some important numbers are key indicators of how well you are managing your condition. Keeping your blood sugar under control can reduce your risk of dangerous diabetes-related complications, such as heart disease, stroke or kidney problems.
Daily blood sugar readings
Testing your blood sugar several times each day with a blood glucose meter, or glucometer, is critical to your health. Self blood sugar checks show exactly what your blood sugar is at the time of the test. These readings show you how meals, exercise, medication, and stress affect your blood sugar and allow you to adjust your diet or medications accordingly to maintain good blood sugar control. It’s recommended that people with diabetes aim to keep blood sugar at the following levels:
- Upon waking: Between 80 and 120 mg/dL
- Before meals: Between 70 and 130 mg/dL
- Two hours after a meal starts: Below 180 mg/dL
- At bedtime: Between 100 and 140 mg/dL
Know that these numbers are just general guidelines. Each person with diabetes will have a slightly different target blood sugar range. Your doctor will let you know yours. He or she can also tell you safe blood sugar levels for before, during and after exercise.
Keep a record of your blood sugar readings and bring it with you to all doctor appointments. These numbers can help your doctor determine if your diabetes care plan is working.
Hemoglobin A1C levels
Daily blood sugar readings don’t show the whole picture, though. They can tell you what your sugar is at a moment in time, but levels fluctuate. Sometimes they’re high and other times they’re low. So how can you know if your diabetes treatment plan is working?
That’s where the hemoglobin A1C test comes in. When you have high blood sugar, more hemoglobin (a protein inside your red blood cells) attaches to the blood sugar in your body. It produces a product called glycated hemoglobin. This is what the A1C test measures. Red blood cells stay in the bloodstream for close to 120 days, or about four months. Measuring the glycated hemoglobin shows what's been happening over this time period. The A1C test shows your average blood sugar levels over the past two to three months. A lower A1C reading means your diabetes is likely under control, and a higher A1C level means your blood sugar has been high.
An A1C level of less than 7 percent is what’s most often recommended for people with diabetes, though your doctor may have a more specific target for you. The goal is to keep your A1C level as close to nondiabetic levels as possible (below 5.7 percent) without having bouts of low blood sugar (hypoglycemia). Keeping your A1C level near goal level will reduce your risk of diabetes-related complications. If your results are high, your diabetes treatment plan may not be working, and your doctor may need to make adjustments.
You’ll need to have the hemoglobin A1C test at least twice a year. Your doctor may run the test more often if your A1C level is high, if your diabetes treatment plan changes, or if you plan to get pregnant.
Other Important Numbers
Your daily blood sugar readings and A1C levels aren’t the only numbers you need to know. Keeping other numbers on target will also help reduce your risk of complications. Following your diabetes treatment plan as prescribed will help you reach these goals:
- Blood pressure: Below 130/70 mmHg
- Cholesterol: LDL (“bad” cholesterol) less than 100 mg/dL; HDL (“good” cholesterol) above 40 mg/dL.
- Waist circumference: A waist measurement of 40 inches or wider for men or 35 inches or wider for women is linked to insulin resistance and increases a person's risk for type 2 diabetes.
- Weight: If you’re overweight, your doctor will give you a weight loss goal
Jenilee Matz is a medical writer, health educator and triathlete based in Charlotte, N.C.