Expert explains how HbA1c test measures blood sugar levels

The HbA1c blood test measures average blood sugar levels over the past two to three months by assessing glucose attached to hemoglobin in red blood cells.

Endocrinologist Dr Pranav Ghody notes that the result represents a weighted average where recent glucose levels exert a greater influence on the final value.

The test result can be converted to estimated average glucose using the standard equation where eAG equals 28.7 multiplied by HbA1c minus 46.7.