What does the 1,5-Anhydroglucitol test measure?

Why is 1,5-Anhydroglucitol measured?

1,5-AG fills a temporal gap between day-to-day capillary glucose monitoring and the three-month average provided by HbA1c. It is particularly sensitive to postprandial glucose spikes and short-term glycaemic variability, making it useful for detecting masked hyperglycaemia in patients whose HbA1c appears acceptable but who experience frequent excursions above the renal threshold. The marker is less informative in advanced renal impairment, where tubular handling is altered, and does not replace HbA1c or glucose monitoring but complements them in selected cases.

Reference ranges

Standard reference

Typically ≥10 µg/mL; lower values indicate recent hyperglycaemic excursions.

Functional medicine optimal

Values ≥14 µg/mL are generally considered to reflect good short-term glycaemic control; values below 10 µg/mL suggest frequent hyperglycaemic excursions warranting intervention.

Units

µg/mL, mg/L

Reference ranges vary by laboratory and assay platform. Interpret in context of the issuing laboratory's stated range.