Complete Blood Count (CBC)Reported in fLMean corpuscular volume (MCV)
The average size of your red blood cells. It is the first index clinicians use to sort out anemia.
What it measures
MCV is measured in femtoliters and answers a simple question: are the red cells small, typical, or large? Small cells are called microcytic, large cells macrocytic. The label is a clue to the cause, not a diagnosis by itself.
Why it is on the panel
Two people can share the same low hemoglobin for completely different reasons. MCV splits those paths. That is why it sits in the middle of every CBC rather than as an optional extra.
How to read it
Read MCV next to RDW. A low MCV with a high RDW often fits iron deficiency, because the marrow is turning out smaller, uneven cells. A low MCV with a normal RDW can fit thalassemia trait. A high MCV points toward B12, folate, alcohol, liver disease, or some medicines.
When it runs higher
Large red cells are common with low B12 or folate, heavy alcohol use, liver disease, an underactive thyroid, and medicines that interfere with DNA synthesis. A slightly high MCV with a normal hemoglobin is something to watch, not an emergency.
When it runs lower
Small red cells are the classic pattern of iron deficiency and of thalassemia trait. Chronic disease and lead exposure can do it too. The iron studies and RDW on this panel help separate those patterns.
How to use this page
This page explains what the measurement is for. It is educational. Your Healiam report includes the reference interval for your age and sex, and a clinician reads that result with your history, medicines, and the rest of the panel. Talk with a clinician before changing diet, supplements, or treatment because of a number on a report.
MCV
MCV is part of the full panel.
No referral or insurance required.
One preventive draw covers this measurement and the rest of the Healiam panel. CLIA-certified results come back in days.