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What is the difference between iron deficiency and B12 deficiency?

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Dr. Guy DaSilva
Preventive Medicine

In brief: The MCV is the clue

When you get a CBC blood test, there is something called the mcv.
This is the red blood cell size. If the cell size or MCV is low, this implies that something is missing in the red blood cell. Since hemoglobin in the rbcs is composed of iron bound to a protein (globulin), it is either iron (common) or globulin & the cell will be small. Low B12 will cause the MCV to be high- poor maturation.

In brief: The MCV is the clue

When you get a CBC blood test, there is something called the mcv.
This is the red blood cell size. If the cell size or MCV is low, this implies that something is missing in the red blood cell. Since hemoglobin in the rbcs is composed of iron bound to a protein (globulin), it is either iron (common) or globulin & the cell will be small. Low B12 will cause the MCV to be high- poor maturation.
Dr. Guy DaSilva
Dr. Guy DaSilva
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