Mean Corpuscular Volume

Haematology marker

MCV

Mean Corpuscular Volume

Category: Haematology
Unit: fL

Average size of red blood cells. Helps classify types of anemia.

PED Notes

Not typically affected by AAS. Low MCV with low iron suggests iron deficiency from blood donations.

When high

When high (>100 fL -- macrocytic, large red cells):

Most common causes: B12 or folate deficiency, alcohol use, hypothyroidism.

Supplements:

  • Vitamin B12 (Methylcobalamin) -- 1000mcg/day sublingual
  • Methylfolate -- 800mcg/day

Follow-up:

  • Check B12, Folate, and TSH
  • Reduce or eliminate alcohol if relevant
  • If B12 and Folate are normal, macrocytosis may be from liver disease or medications

How to read red cell indices as a set rather than one flagged number: The complete haematology panel for enhanced athletes.

When low

When low (<80 fL -- microcytic, small red cells):

Most common cause in AAS users: Iron deficiency from regular blood donation to manage high haematocrit.

Supplements:

  • Iron Bisglycinate -- 25-50mg/day with Vitamin C 500mg for absorption
  • Take iron on empty stomach or with Vitamin C; avoid calcium, coffee, tea within 2h

Follow-up:

  • Check Ferritin, Serum Iron, Transferrin Saturation to confirm iron deficiency
  • Recheck MCV after 8-12 weeks of iron supplementation (red cell turnover takes time)
  • If MCV remains low with adequate iron, investigate thalassaemia trait (common genetic cause)

Educational information, not medical advice. Nothing here is a prescription or a treatment plan, and it does not account for your history, medications or conditions. Use it to ask better questions: bring it to your doctor and decide together. Full disclaimer.

History Chart

Reading History

Frequently Asked Questions

Reference Ranges

Standard Range

80 - 100 fL

Statistics