Glycated hemoglobin A1C

GLYCATED HEMOGLOBIN A1C (HBA1C)

The hemoglobin in red blood cells is glycated by the glucose present in the blood. Glycated hemoglobin levels represent the average blood sugar levels within 2–3 months. If the glucose levels have been elevated during this period, the hemoglobin A1C test will also produce higher than normal results. This is indicative of blood sugar dysregulation, insulin resistance or diabetes.

HbA1C values may also be affected by individual factors, particularly concerning nutrition, which may skew the results somewhat. A study found the lifespan of red blood cells in diabetics to be only 81 days whereas for non-diabetics it was 146 days. The longer the lifespan of the red blood cell, the more it binds glucose (becomes glycated). This may raise the values disproportionately without indicating insulin resistance or pre-diabetes. This may be relevant in cases where the fasting blood sugar and insulin levels are optimal yet the HbA1C level is surprisingly high.

• Normal: 20–42 mmol/M / 4.0%–6.0%
• Optimal: 20–34 mmol/M / 4.0%–5.3%

Abnormal factors may include anemia (excessively low value) or dehydration (excessively high value).