HbA1c: Your Key to Understanding Average Blood Sugar
You're likely familiar with terms like "blood sugar" and "insulin," especially if you're managing diabetes, prediabetes, or are at risk. However, another crucial term to understand is Hemoglobin A1c (HbA1c). This test provides a vital insight into your average blood sugar levels over an extended period, offering a more comprehensive picture than a single blood sugar reading.
What is HbA1c, Anyway?
Think of hemoglobin as a tiny taxi inside your red blood cells, mostly responsible for carrying oxygen throughout your body. But sometimes, sugar (glucose) molecules hitch a ride on these taxis. Everyone has some sugar attached to their hemoglobin.
Here's the key difference: when you check your blood sugar at home, it's just a snapshot of that moment. Your blood sugar goes up and down all day depending on what you eat, how much you exercise, and even when you sleep.
However, an HbA1c test gives you a bigger picture. It tells you your average blood sugar levels over the past three months. As Dr. David M. Nathan, a Harvard Health Publishing expert, explains, "All of us, diabetic and nondiabetic alike, have blood sugar levels that fluctuate constantly." But for people with diabetes, those blood sugar levels are consistently higher.
How Do You Get Your HbA1c Measured?
Getting your HbA1c checked is simple. Your doctor can do it with a quick finger prick (you'll get results right away!) or by drawing a small vial of blood from your arm (results usually come back within a day). The best part? You don't need to fast or prepare in any special way.
Regular HbA1c tests are a standard part of care for anyone with or at risk for diabetes. It helps you and your doctor see how your blood sugar has been trending over time. This way, you can catch rising levels early and take steps to bring them down, either to prevent diabetes or to manage it effectively. It's also a great way to see if your current treatment plan is working or if it needs a tweak.
Understanding Your HbA1c Numbers
While your daily blood sugar checks are in "mg/dL," your HbA1c is given as a percentage. This percentage tells you how much sugar is attached to your hemoglobin taxis.
Below 5.7%: This is considered normal. Your blood sugar levels are healthy.
5.7% to 6.4%: This range means you have prediabetes. Dr. Nathan calls this a "wake-up call." It's a sign that your blood sugar levels are starting to climb, and it's time to consider changes like losing some weight or becoming more active.
6.5% or higher: This indicates diabetes.
Why Your HbA1c Goal Matters if You Have Diabetes
If you have diabetes, your doctor will set a personalized HbA1c goal for you. For many, the aim is below 7%. Keeping your HbA1c in check is super important because high levels over time are the biggest risk factor for serious diabetes complications. As Dr. Nathan warns, this can include "eye disease that can result in blindness, kidney disease that can cause kidney failure, and nerve disease (neuropathy) that can lead to the need for amputation."
While these complications usually take many years to develop, it's crucial not to be complacent. Managing your blood sugar, blood pressure, and cholesterol over time is the best way to stay healthy and avoid these issues. (Note: For older adults, the A1c target might be a bit higher, as they're less likely to develop these long-term complications, which take a long time to show up.)
How to Lower Your Blood Sugar and HbA1c
If your HbA1c is higher than it should be, don't worry! You and your doctor can create a plan to bring those numbers down. This plan often involves changes to your diet, regular exercise, and sometimes medication.
One of the most effective ways to lower blood sugar is by losing extra weight. Even shedding 7% to 10% of your body weight can make your cells more sensitive to insulin, which helps regulate blood sugar. Diet and exercise are key here.
Diet: The best eating plan is one that fits your life, but here are some general tips for stable blood sugar:
Eat smaller meals throughout the day.
Fill most of your plate with non-starchy veggies (think leafy greens, broccoli, peppers).
Choose lean meats or plant-based proteins.
Cut back or cut out added sugars.
Opt for healthy fats like olive oil.
Focus on whole, unprocessed foods.
Drink plenty of water.
Exercise: Make physical activity a regular part of your routine. Aim for at least 150 minutes per week of heart-healthy activities like brisk walking or cycling.
Medication: If diet and exercise aren't enough, your doctor might prescribe medication. Metformin is often the first choice for diabetes treatment. Other options include various types of medications that can be added if your blood sugar and HbA1c remain above your goal.
Knowing your HbA1c is a powerful tool in managing your health. If you have questions about your HbA1c levels or how to keep your blood sugar in a healthy range, talk to your doctor.
Source: Harvard Health | June 30, 2025