Archive · 1 Sep 2026
High Glucose With Low HbA1c Requires Medical Evaluation
A blood-glucose reading tells you what your sugar level is at one moment.
HbA1c gives an estimate of your average sugar level over the last two or three months.
Sometimes these two measurements do not agree.
This can happen if red blood cells do not live for their usual length of time.
Anaemia, blood loss, transfusions, kidney disease and some haemoglobin types can affect the HbA1c result.
A faulty or unsuitable testing method can also interfere with the result.
Repeated readings between 160 and 220 mg/dL should not be ignored just because HbA1c is below 6%.
A doctor can confirm the results and may use other tests to assess glucose control.
Repeated glucose readings of 160–220 mg/dL are significant even when HbA1c is below 6%.
HbA1c estimates average glucose over roughly two to three months, while a glucose reading is a snapshot.
A falsely low HbA1c can result from rapid red-cell turnover, anaemia, blood loss, transfusion, kidney disease or haemoglobin variants.
HbA1c test methods may be affected by haemoglobin variants such as HbE and other haemoglobinopathies.
Doctors may verify readings, repeat HbA1c testing and use fructosamine or glycated albumin if needed.
- Who
- People with repeated glucose readings of 160–220 mg/dL and an HbA1c below 6%; Dr Pranav Ghody provided the medical explanation.
- What
- The article explains why blood-glucose readings and HbA1c results can disagree and how doctors may investigate the mismatch.
- When
- The glucose readings are reportedly repeated; HbA1c reflects approximately the previous two to three months, while each glucose reading is a snapshot.
- Where
- The medical guidance was provided by Dr Pranav Ghody of Wockhardt Hospitals, Mumbai Central.
- Why
- The discrepancy may result from red-cell conditions, kidney disease, haemoglobin variants or testing-method interference, and persistent high glucose may have health consequences.
- Reported glucose range
- 160–220 mg/dL
- Reported HbA1c
- Below 6 per cent
- HbA1c timeframe
- Approximately two to three months
- Possible causes of falsely low HbA1c
- Anaemia, recent blood loss or transfusion, increased red-cell turnover, kidney disease and haemoglobin variants
- Relevant haemoglobin variants
- HbE and other haemoglobinopathies
- Possible verification methods
- A reliable glucometer or, where appropriate, a continuous glucose monitor
- Alternative tests
- Fructosamine or glycated albumin may provide shorter-term glucose assessment if HbA1c is unreliable