Fructosamine
Fructosamine measures glucose that has attached to proteins in your blood, mainly albumin. Because these proteins turn over faster than red blood cells, it reflects your average blood sugar over roughly the past two to three weeks.
Fructosamine offers a shorter-term view of blood sugar than HbA1c, which can be helpful when recent changes matter or when HbA1c may be unreliable. It is sometimes used when conditions affecting red blood cells make HbA1c harder to interpret. This makes it a useful alternative window into glucose control.
A higher fructosamine generally suggests your average blood sugar has been elevated over the past few weeks. Because it depends on blood protein levels, conditions that lower albumin or change protein turnover can affect the result. Your clinician interprets it in light of those factors.
A lower fructosamine usually reflects average blood sugar in a healthy range over recent weeks. Low protein or albumin levels can also pull the value down independent of your glucose.
Reference ranges for fructosamine vary by lab, so there is no single universal target. Your clinician will interpret your result against your lab's range and your situation.
Sources
Educational context only, not medical advice or a diagnosis. Reference ranges vary by lab, age and sex; always discuss your results with a clinician.