Retest date planner

Why ~90 days?

A1C reflects the amount of glucose attached to hemoglobin in your red blood cells — and red blood cells live for about three months. That makes A1C a slow-moving, three-month average rather than a snapshot of any single day. Retest much sooner than ~90 days and the lab is largely re-measuring the same cells, so the number has had little room to change. This is population-level education about how the test works, based on ranges and guidance published by the American Diabetes Association — your own retest timing is a conversation with your healthcare provider, who may suggest a shorter or longer window.

What to bring to the follow-up

• Your previous results — the last A1C (and any other labs), so you and your provider can compare like for like.
• Notes on what changed — activity, meals, sleep, stress, weight. Even rough notes give the new number context.
• A short list of questions — three is plenty. Appointments go fast.
• Your current medications and supplements — including anything you started or stopped this cycle.
• The date you planned here — so the next cycle starts with a clear finish line.