The MCV Blood test is one component of the Complete Blood Count, one of the most common tests you will have, and usually part of your regular checkup at the doctor’s office. Specifically, it is a measure of the average size of your red blood cells to ensure that they are normal. If they are too small or too large, that could be an indication of an underlying health issue.
Let’s take a closer look at this specific test to see what it is all about…
The MCV Blood Test – An Introduction
There are basically two reasons why your doctor might order an MCV blood test. It will either be a routine part of your yearly checkup or he/she might be trying to diagnose/monitor a health issue. It is one component of the CBC, or Complete Blood Count, which is a comprehensive analysis of your blood cells and platelets. The CBC test provides a wealth of information about how your body is functioning, which is why it is an integral part of your wellness checkup.
While the CBC test measures your red and white blood cells, hemoglobin, hematocrit and platelets, the MCV Blood Test focuses on just the red blood cell component.
MCV stands for Mean Corpuscular Volume, and the test involves a measurement of the average size of your red blood cells. Remember, your red blood cells move oxygen around your body, a necessary process for optimal health. If they are not functioning properly, your overall health can suffer.
So the MCV blood test is checking the average size of all of your red blood cells to see if it’s within a normal range.
What Does it Mean if MCV Blood Test is High?
The MCV blood test results are measured in something called a femtolitre, which is a metric unit equivalent to 1 quadrillionth of a liter. The normal range for an adult is between 80 and 100 femtoliters, although these numbers will vary from one lab to the next.
If your MCV Blood test is high, meaning a result of over 100 fL, this means that your red blood cells are larger than they should be. This is a condition called macrocytic anemia, and it can be caused by a number of things including a Vitamin B9 or B12 deficiency, chemotherapy, liver disease, thyroid malfunction and heavy metals. More often than not, the deficiency is to blame, which is why the B vitamins are so important for the heart and cardiovascular system.
There are a number of symptoms of macrocytic anemia, but they can often be quite similar to those present in other health conditions. That’s why the MCV blood test is important in making a proper diagnosis. These symptoms can include fatigue, dizziness, cold hands/feet, decreased hunger, memory loss, shortness of breath and pale skin. As you can see these are very common signs of many different ailments.
If your MCV blood test is high, your doctor will properly order some follow up tests to confirm a diagnosis of macrocytic anemia. As the most common cause is a B12 and/or folate (B9) deficiency, doctors will usually recommend a diet high in these two important nutrients.
It’s important to know that vegans are often B12 deficient, as the only real source of Vitamin B12 is animal products. So unless they are eating B12 fortified foods, vegans are at a much higher risk for elevated MCV blood test results than others.
Vitamin B12 is found in high concentrations in red meat, fish, chicken, eggs and fortified foods.
Folate is found in high concentrations in citrus fruit, dark leafy greens like spinach, beans and avocados, which are also good for lowering cholesterol.
Following a determined period of time after you make these dietary changes, and take supplements if necessary, your doctor will order another MCV Blood Test to see if your red blood cells have returned to normal size. If not, he or she will figure out another course of action.
What Does it Mean if MCV Blood Test is Low?
If your MCV blood test is low, with the number being under 80 fL, that means your red blood cells are smaller than they should be. This condition is called microcytic anemia, and this is usually caused by an iron deficiency that is preventing your body from making enough hemoglobin. This is a compound that gives blood its red color, and helps move oxygen around your body.
It’s interesting to note that microcytic and microcytic anemia can hand the same symptoms, including shortness of breath, fatigue, dizziness and pale skin. So whether your red blood cells are too big or too small, you might experience the same signs. That’s why the test is so important.
There are several types of microcytic anemia, all with varying degrees of hemoglobin present in the blood. But the most common is hypochromic, meaning there simply isn’t enough hemoglobin being produced.
Once a proper diagnosis is made, and the cause is determined to be an iron deficiency (although other causes are possible) your doctor will typically prescribe iron supplements, along with Vitamin C to help with the absorption. As with high MCV blood test results, low results can also be corrected with proper treatment. A follow up test will determine if the iron supplementation was successful.
Other Red Blood Cell Tests
In addition to the MCV blood test, another part of the CBC is the MCH test, which is often confused for the MCV. The MCH test measures the amount of hemoglobin in each red blood cell. There is also the MCHC test, which related the amount of hemoglobin to the size of the cell.
The MCH and MCHC results are measured differently than the MCV blood test results. The normal range of the MCH test is between 27 and 31 picograms per cell. The normal range of the MCHC test is between 32 and 36 grams per deciliter.
Together all three of these tests: MCV, MCH and MCHC give doctors a very good picture of the health and function of your red blood cells. They are combined with a total count of the cells to help doctors decide if everything is normal as far as your red blood cells are concerned.
MCV Blood Test – Summary
It’s important to be aware of the fact that sometimes the numbers are incorrect, and just because your MCV blood test comes out high or low, doesn’t mean you necessarily have anemia. Doctors will take a look at the entire CBC to make a determination, and order a re-test if something doesn’t add up.
Even if the results are accurate, there is no need to panic. More often than not macrocytic and microcytic anemia can be treated successfully with dietary changes and/or supplementation. There are cases where something else might be at play, but your doctor should be able to make an accurate diagnosis and come up with an appropriate treatment protocol.