HbA1c (glycated haemoglobin) is the cornerstone blood test for diabetes monitoring. It measures the percentage of haemoglobin molecules that have glucose attached — reflecting average blood sugar levels over the preceding 8–12 weeks. A single HbA1c result is useful; a series of results tracked over time is genuinely insightful.
What the numbers mean
- Below 42 mmol/mol (6.0%) — non-diabetic range
- 42–47 mmol/mol (6.0–6.4%) — prediabetes; lifestyle intervention strongly recommended
- 48 mmol/mol (6.5%) or above — diagnostic for diabetes on two occasions
- Target in type 2 diabetes — typically 48–53 mmol/mol (6.5–7.0%); individualised for age and comorbidities
- Target in type 1 diabetes — typically below 48 mmol/mol (6.5%); higher in those at risk of hypoglycaemia
Why the trend matters more than a single reading
An HbA1c of 58 mmol/mol (7.5%) is very different depending on where it's come from. If your last three results were 72, 65 and 58, that's a clear improvement — your management changes are working. If they were 46, 50 and 58, that's a worsening trend requiring attention and possibly a medication change.
Tracking HbA1c over time in Looms plots each result on a chart so you and your doctor can see the direction of travel immediately, rather than comparing numbers mentally across different paper reports.
"A single HbA1c is a checkpoint. A series is a story — and the story is what guides treatment."
Omar Khalil, Health Educator