Key Points
- The A1C blood test is used to diagnose or manage diabetes. It measures your average blood sugar level over the past three months. High A1C levels may indicate diabetes or prediabetes, but can also be caused by other health conditions such as anemia, kidney disease, and liver disease.
- High A1C levels can also be caused by conditions such as anemia, kidney disease, high triglycerides, spleen disorders, thyroid disorders, certain medications, recent blood transfusions, and certain ethnic backgrounds.
- If your A1C levels are high but you do not have diabetes, your doctor may conduct other lab tests to identify the root cause, and usually recommends an A1C test for those who are at risk for diabetes mellitus or gestational diabetes.
- The National Institutes of Health (NIH) suggests that high A1C levels can be reduced naturally through healthy lifestyle behaviors, eating foods that are low on the glycemic index, increasing physical activity, weight loss, and maintaining an overall healthy lifestyle.
- Other factors that can help lower A1C levels include lifestyle changes like reducing alcohol intake, stopping smoking, reducing high blood pressure, and managing other medical conditions.
The A1C test (also known as a hemoglobin A1C (or HbA1C) test) measures your average blood sugar level over the last three months. This test is commonly used to help people with type 1 diabetes, type 2 diabetes, prediabetes, or gestational diabetes manage their conditions. This test may also be used in nondiabetic adults who have a family history of diabetes, are at a higher risk of developing diabetes, or have other conditions that affect their glucose tolerance. Hemoglobin A1C levels are also measured to see how well diabetes treatment is going.
While A1C is commonly used to evaluate diabetes (a chronic condition that affects your pancreas and insulin levels), you can have a high A1C result and still not be diabetic, according to the NIH.
What is A1C and an A1C test?
The NIH defines hemoglobin A1C as a protein in red blood cells that carries oxygen from your lungs to the rest of your body. Blood sugar binds to hemoglobin in the blood cells. If your blood sugar level is high, a large amount of it will attach to hemoglobin, which is why this test is commonly used to check and manage diabetes.
The A1C test measures the amount of blood sugar that is attached to hemoglobin. According to the NIH, this diabetes test measures average blood sugar levels over the last three months because three months is the average lifespan of a red blood cell. High HbA1C levels indicate high blood sugar levels (hyperglycemia) and may mean that you have diabetes or prediabetes (a condition that is close to progressing into diabetes). Diabetes is not the only thing that can affect your A1C test. According to the NIH, the following factors can also change your A1C:
- Certain medications
- Being anemic
- Having chronic kidney disease
- High triglycerides
- Problems with your spleen
To get an A1C test you will have to give a blood sample. This is usually done at a laboratory or a healthcare professional's office. You can usually request this test yourself, or your doctor may request it if you have a high fasting glucose or risk factors that put you at higher risk for diabetes.
Understanding Normal A1C Levels
Reading your A1C levels may seem overwhelming if you're not familiar with them. But understanding your levels is important—levels outside a normal range should be discussed with a doctor so you can be sure to get any treatment you may need as soon as possible.
According to the Centers for Disease Control and Prevention, normal A1C levels are levels below 5.7%. This level means your average blood glucose levels are within normal limits and you likely don't have diabetes or prediabetes. But, if you are at increased risk for diabetes, your healthcare provider may still recommend regular testing in the future, according to the American Diabetes Association.
A slightly elevated A1C is between 5.7% and 6.4%, according to the CDC. This result may indicate that you have prediabetes. A high A1C is a level of 6.5% or above and may indicate diabetes, the CDC also notes.
High A1C Levels Without Being Diabetic: Is it Possible?
High A1C levels do not always necessarily mean that you have diabetes. The NIH reports that high A1C causes include blood disorders like anemia, as well as liver disease, kidney failure, and sickle cell disease.
If your A1C level is high, your doctor may perform a blood glucose test to diagnose or rule out diabetes. If you do not have diabetes, your doctor may order another type of lab test to identify the root cause of high A1C.
8 Reasons for High A1C Levels
The NIH states there are several potential causes of elevated HbA1C without diabetes. Knowing more about these conditions can help you determine whether you may be at risk and need treatment.
1. Anemia
Anemia is a condition in which your blood is unable to carry enough oxygen to the rest of your body. Anemia is usually caused by iron deficiency, as iron is needed to make hemoglobin, reports the NIH. Next to diabetes, anemia is one of the top causes of high A1C.
2. Kidney disease and disorders
Kidney problems usually occur when the kidneys become damaged and can no longer filter blood properly. This can cause high levels of sugar to build up in the bloodstream and contribute to high A1C, according to the NIH.
3. High triglycerides
Triglycerides are a type of fat in your body that comes from foods such as butter and oils. According to the NIH, high triglycerides can affect your heart and blood health by causing elevated A1C.
4. Spleen disorders
The NIH states that your spleen is partly responsible for fighting infection, balancing body fluids, and destroying old and damaged blood cells. A spleen disorder can impair your body’s ability to destroy old blood cells, which can eventually lead to high A1C.
5. Thyroid disorders
The thyroid is a small gland shaped like a butterfly that is located at the base of the front of your neck. Your thyroid is responsible for making a series of hormones that control your metabolism. According to a 2010 study published in Diabetes Care, thyroid disorders and abnormal thyroid levels can lead to elevated A1C in people who do not have diabetes.
6. Certain medications
Large doses of aspirin, HIV medications, and chronic use of opioids may contribute to elevated A1C in people with diabetes, according to a 2012 study published in the Indian Journal of Endocrinology and Metabolism.
7. Donated blood
You may have high A1C levels if you recently had a blood transfusion. According to a 2017 study in PloS One, blood that comes from a donor could result in high or lower A1C and affect your A1C readings.
8. Ethnicity and background
Certain ethnic groups may have higher A1C levels than others. The NIH reports it is currently conducting clinical trials to determine why certain racial and ethnic groups may be predisposed to high A1C.
How to Lower Your A1C Levels Naturally
If you have high A1C levels, the NIH suggests that it’s possible to reduce your levels of this protein naturally through a series of healthy lifestyle behaviors.
Diet
According to the NIH, foods that are high in sugars and unhealthy fats may lead to a higher blood sugar level and A1C reading. Modify your diet to include more fruits, vegetables, lean proteins, nuts, seeds, fish, poultry, and whole grains. Eat fewer carbohydrates, including bread, candy, and ice cream. According to the Utah Department of Health, a diet high in carbohydrates will cause sugar to build up in the bloodstream at a high rate.
Exercise
Exercise naturally reduces A1C by moving sugar from your bloodstream and into your muscles. The NIH recommends that you start exercising regularly on most days a week, even if you start small by walking for 15 minutes a day. Gradually increase your activity level week by week, and stick to doing activities you truly enjoy, such as dancing, gardening, and yoga.
Lifestyle
An overall healthy lifestyle can reduce your risk for most illnesses and diseases, including diabetes, according to data from the NIH. Habits like, watching less television and spending more time outdoors in the sun being active, may help contribute to a healthy lifestyle. Reducing your alcohol intake and stopping smoking, while eating a higher amount of healthy foods, are also recommended by the NIH. Other important habits may include, getting plenty of quality sleep, and spending more time with positive, like-minded people who make you feel good about yourself.
Frequently asked questions
What causes high A1C?
High A1C is caused by having an elevated blood sugar level over a period of three months. According to the NIH, the most common high A1C causes and risk factors include diabetes, anemia, lack of exercise, and obesity.
What can falsely elevate A1c?
The NIH reports that several factors can falsely elevate your A1C. These factors include recent blood loss, sickle cell disease, blood transfusion, and iron deficiency.
What does A1C stand for?
A1C stands for glycated hemoglobin, or hemoglobin A1C (HbA1C), according to the NIH.
What is a good A1c for a non-diabetic?
A normal A1C reading is below 5.7%, while an A1C reading for prediabetes ranges between 5.7% and 6.4%, reports the NIH.
Where can I get an A1C lab test?
A1C lab tests are widely available and easy to find when you use Solv. Solv can give you a list of high-quality diabetes test providers in your area that offer the A1C test. Use Solv to access convenient and hassle-free health care, and make a same-day appointment for an A1C test at an urgent care clinic in your area.
Can fasting cause high A1C?
Fasting can potentially help improve A1C levels, according to the NIH. When the body is fasting, it relies on stored glucose for a time, which can help stabilize high blood sugar levels. However, it's important to note that the impact of fasting can vary from person to person, and it's always a good idea to consult with a healthcare professional for personalized advice.
What should I avoid before the A1C test?
According to the Mayo Clinic, you do not need to fast or do anything else to prepare for the A1C test. They recommend that you eat and drink normally before your test.
Can stress cause high A1C?
Stress, especially prolonged stress, can have many negative effects on your body—including on your blood sugar, according to Healthline. They note that stress can raise blood sugar levels and increase insulin resistance. In turn, this can cause a high A1C result.
How many days does it take to lower A1C?
Although you can lower your blood sugar within minutes to hours, lowering your A1C will take longer. Because your A1C is an average of your blood sugar levels over a few months, it will take a least a few months to lower your A1C. There are several things you can start doing now to manage your diabetes and lower your A1C.