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What MCV Levels Mean (Mean Corpuscle Volume)
Updated on November 13, 2023
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What MCV Levels Mean (Mean Corpuscle Volume)

Key Takeaways

Mean corpuscular volume or mean cell volume (MCV) describes the average size of your red blood cell (RBC) in a blood sample. It is often part of a complete blood count (CBC), which looks at RBCs and other components in your blood.

Red blood cells (RBCs) deliver oxygen and vital nutrients to every cell and tissue in the body. They must be the right shape, size, and capability to perform this function.

“MCV is a measurement of the approximate size of your RBCs,” says our in-house medical reviewer Dr. Rizza Mira. 

When your RBCs are too small or too big, they don’t carry oxygen efficiently. If this happens, you may have a higher risk of developing certain types of anemia.

“This is why doctors recommend an MCV blood test for people with symptoms of anemia,” she explains.

A person can have high, normal, or low MCV levels. Let’s find out what they mean about your health.


Mean corpuscular volume (MCV) measures the average size of red blood cells in a blood sample, MCV levels can be high, normal, or low and can indicate the risk of developing certain types of anemia.

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What is an MCV Blood Test?

The MCV blood test measures the average size of your red blood cells (RBCs). It’s one of the tests included in a complete blood count (CBC).

A CBC looks at the different types of cells in your blood, including RBCs, white blood cells (WBCs), and platelets.

Other RBC indicators include:

  • Mean corpuscular hemoglobin (MCH): Average hemoglobin level in an RBC
  • Mean corpuscular hemoglobin concentration (MCHC): Average hemoglobin concentration in RBCs
  • Red cell distribution width (RDW): A measure of size variations in your RBCs

Hemoglobin is the protein in your RBCs that carries oxygen.

Doctors may order a CBC as part of a routine blood test. But they can also use it to screen for various health issues. 

What Does MCV Mean In A Blood Test?

Doctors use MCV blood tests alongside other tests to diagnose certain blood disorders, like anemia. Anemia occurs when the body doesn’t produce enough healthy red blood cells.

Your MCV levels help doctors determine your type of anemia and what may be causing it.

Anemia caused by abnormal RBC size can be one of three types

  • Microcytic - occurs when the circulating RBCs are smaller than the standard size
  • Macrocytic - happens when there are more overly large RBCS than normally sized RBCs
  • Normocytic - occurs when your RBCs are normal in size but lower than the normal count


Mean corpuscular or mean cell volume (MCV) is a measurement of the approximate size of your red blood cells. It's often listed in a complete blood count (CBC). Doctors use the results of an MCV blood test to diagnose blood disorders like anemia.

What Is An Elevated MCV?

An elevated MCV means a value above 100 fL.1 High MCV levels mean your red blood cells are larger than usual. 

These RBCs are also “poorly nourished,” says Dr. Mira. They’re unable to carry around hemoglobin throughout your body efficiently.

What Does High MCV Mean?

A high MCV level suggests you may have macrocytic anemia. The following factors may cause macrocytic anemia:2

  • Vitamin B12 or B9 (folate) deficiency
  • Liver disease   
  • Pernicious anemia 
  • Hypothyroidism

People who follow a vegan diet are at a higher risk of B12 deficiency. Gut disorders such as Crohn’s disease that affect B12 absorption can also lead to deficiency and anemia.7 


An elevated MCV indicates the red blood cells are larger than usual and unable to carry hemoglobin efficiently. This suggests a person may have macrocytic anemia caused by factors such as vitamin B12 or B9 deficiency, liver disease, pernicious anemia, or hypothyroidism.

What Is Low MCV?

A low MCV level is anything below 80 fL.1 It means your RBCs are smaller than normal.

What Low MCV Means

Low MCV levels suggest you have microcytic anemia. Microcytic anemia usually occurs when your body doesn't make enough hemoglobin. As a result, your red blood cells are smaller. 

Iron deficiency anemia (IDA) often causes microcytic anemia. The most common causes of Iron deficiency anemia include:

  • Not eating enough iron-rich foods
  • Gut disorders that impair its absorption
  • Increased demand for iron due to pregnancy or surgery

Aside from IDA, these health factors may also cause macrocytic anemia:2

  • Thalassemia or an inherited blood disorder occurring when your body doesn't make enough hemoglobin
  • Copper deficiency
  • Vitamin A deficiency
  • Chronic inflammatory diseases
  • Lead poisoning


Low MCV levels refer to smaller than normal red blood cells. It may suggest microcytic anemia, which is ypically caused by iron deficiency. Other possible causes include inherited blood disorders, vitamin or mineral deficiencies, and chronic inflammatory diseases.

What Factors Can Affect Your MCV Level

Certain factors can affect your MCV results. Some of them can raise or lower your MCV.

Factors that can raise your MCV level

  • Excessive alcohol consumption
  • Frequent smoking
  • Vitamin B12 and folate deficiency4
  • Overuse of medications like proton pump inhibitors (PPIs) and metformin4
  • Chronic stress5

Factors that can lower your MCV level

  • Frequently donating blood that leads to depleted iron stores in your body6

What Is The Normal MCV Range?

The normal MCV range for most healthy people is 80 to 100 fL (femtoliter).1 It means your red blood cells are a healthy size.

What Normal MCV Levels Mean

A normal MCV level means you have normal-sized RBCs. However, despite having a normal MCV, you can still develop anemia— a condition known as normocytic anemia.1

Normocytic anemia happens when your RBCs are of standard size but cannot carry hemoglobin.

In addition to your MCV, doctors may look at your hematocrit and hemoglobin. You may have normocytic anemia if your MCV is normal, but these levels are low.

Your hematocrit level shows how much of your blood comprises RBCs. On the other hand, your hemoglobin level reveals how much hemoglobin is in your blood. 

The following health conditions can also cause normocytic anemia:2 

  • Kidney failure
  • Aplastic anemia
  • Chronic inflammatory diseases
  • Autoimmune diseases
  • Infections
  • Cancer

Doctors can also use other tests like a blood smear to investigate your anemia's cause further.


Many factors affect your MCV levels, causing them to go up or down the normal range. However, having a normal MCV range can still put you at risk of developing anemia. It happens when your red blood cells are normal in size but aren't capable of carrying hemoglobin.

When Should You Get Your MCV Levels Tested

Mean corpuscular volume is one of the red blood cell indices. It’s part of the blood tests that help assess your red blood cells' size, shape, and quality. 

Besides a routine health exam or diagnostic testing, your doctor may ask to test your MCV level if you have symptoms of anemia. 

The early signs of anemia may include

  • Feeling tired or weak more than usual
  • Tingling or numbness feeling in your hands and feet
  • Loss of appetite
  • Irritability
  • Having trouble concentrating or thinking
  • Shortness of breath
  • Mouth ulcers
  • Dizziness or lightheadedness when you stand up
  • Nails that break easily
  • Pale skin color
  • Unusually red tongue
  • Abnormal menstrual bleeding

How To Test Your MCV Levels

Your doctor will order an MCV test as part of a CBC. Make sure to let your doctor know if you are experiencing any symptoms of anemia.

An MCV blood test requires your blood sample. You can usually get tested for it in a hospital, medical clinic, or laboratory. 

If you're just getting a CBC done, you don’t have to do anything to prepare for the test. If you’re getting other tests done, your doctor may require you to fast for a certain period.

After submitting your blood sample, you should receive your results within a few days. If you are diagnosed with anemia, your doctor may order additional tests to determine the cause.


MCV testing is a blood test to assess red blood cells' size, shape, and quality. A doctor may request an MCV test if a person shows symptoms of anemia, such as fatigue, pale skin, and shortness of breath. MCV testing requires a blood sample, and results can usually be obtained within a few days.

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Updated on November 13, 2023
Dr. Rizza Mira
Dr. Rizza Mira
Medical Reviewer
Dr. Rizza Mira is a medical doctor and a general practitioner who specializes in pediatrics, nutrition, dietetics, and public health.

As a pediatrician, she is dedicated to the general health and well-being of children and expecting parents. She believes that good nutrition, a healthy lifestyle, and prevention of illness are key to ensuring the health of children and their families.

When she’s not in the hospital, Rizza advocates and mobilizes causes like breastfeeding, vaccination drives, and initiatives to prevent illness in the community.
Will Hunter
Will Hunter
Content Contributor
Will is a content writer for KnowYourDNA. He received his B.A. in Psychology from the University of California, Los Angeles. Will has 7 years of experience writing health-related content, with an emphasis on nutrition, alternative medicine, and longevity.
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