Planning Medical Tests and Health Screenings in South Korea

Hemoglobin A1C is a blood test that measures the average blood sugar level over the past two to three months. It is commonly used to diagnose diabetes and prediabetes, as well as to monitor how well diabetes is being managed. The test measures the percentage of hemoglobin proteins in red blood cells that have glucose attached to them. Since red blood cells live for approximately three months, the A1C test provides a longer-term view of blood sugar control compared to daily glucose monitoring.

For people without diabetes, a normal A1C level is below 5.7 percent. An A1C level between 5.7 and 6.4 percent indicates prediabetes, which means blood sugar levels are higher than normal but not yet high enough to be classified as diabetes. An A1C level of 6.5 percent or higher on two separate tests indicates diabetes. For those already diagnosed with diabetes, the American Diabetes Association generally recommends an A1C target of less than 7 percent, though individual goals may vary based on age, overall health, and other factors.

The A1C test offers several advantages over other glucose tests. It does not require fasting, so it can be performed at any time of day. It is less affected by short-term factors like stress, illness, or recent meals that can cause temporary spikes or drops in blood sugar. The test provides a more comprehensive picture of blood sugar control over time, making it easier to assess the effectiveness of diabetes treatment plans.

Certain conditions can affect the accuracy of A1C results. People with certain types of anemia, recent blood loss, or blood transfusions may have inaccurate readings. Certain hemoglobin variants, more common in people of African, Mediterranean, or Southeast Asian descent, can also interfere with some A1C test methods. In these cases, healthcare providers may use alternative testing methods or additional tests to accurately assess blood sugar control. Regular A1C testing, typically every three to six months for people with diabetes, helps ensure that treatment plans are working effectively and allows for timely adjustments when needed.