Hemoglobin A1c

also known as HbA1c

NORMAL_RANGE
4 – 5.6 %
UNIT
%

/WHAT_IT_IS

HbA1c measures average blood sugar over the prior 3 months by tracking glycated hemoglobin. It's the gold standard for diagnosing and monitoring diabetes.

/NORMAL_RANGE

Reference: <5.7%. 5.7–6.4% = prediabetes. ≥6.5% on two occasions = diabetes. Optimal for most men: 5.0–5.4%.

What does high HbA1c mean?

  • +Insulin resistance, type 2 diabetes, chronic high-carb intake, weight gain.
  • +Polycythemia/high RBC can falsely lower A1c — interpret with caution on TRT.

What does low HbA1c mean?

  • +Anemia, hemolysis, recent blood loss (artifactually low).
  • +Genuinely good glycemic control.

/ON_TRT

TRT typically improves insulin sensitivity and reduces HbA1c by 0.2–0.5% over 12 months. However, the high hematocrit common on TRT can falsely lower A1c readings — if your A1c trends down while glucose stays the same, look at HCT before celebrating.

/RELATED

/TRACK_THIS

Track HbA1c in the app.

Upload your lab PDF — MyTRT extracts every marker with Gemini Vision. Charts, trends, and TRT-aware insights. Free on iOS and Android.

Last reviewed: 2026-06-04 · MyTRT does not provide medical advice. Always consult your physician.