MCH levels in blood tests: What do they mean

At first, many people with low MCH levels do not experience symptoms at all. When low MCH numbers persist or fall too low, symptoms start to appear. Symptoms of low MCH include:

What Are MCH Levels?

You might hear your doctor talk about MCH levels when they explain the results of certain blood tests. MCH is short for “mean corpuscular hemoglobin.” It’s the average amount in each of your red blood cells of a protein called hemoglobin, which carries oxygen around your body.

It’s possible you’ll learn about MCH when you get a blood test called a CBC (complete blood count). This test measures different parts of your blood, including red blood cells and white blood cells. Doctors use information from the CBC to calculate your MCH.

A similar measure to MCH is something doctors call “mean corpuscular hemoglobin concentration” (MCHC). MCHC checks the average amount of hemoglobin in a group of red blood cells.

Your doctor may use both measurements to help in a diagnosis of anemia. It’s a condition caused by not having enough healthy red blood cells, or the red blood cells you do have don’t work as well as they should. Anemia can make you feel extremely tired.

Getting a CBC

A CBC measures the different cells that make up your blood, including your:

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Red blood cells
White blood cells, which fight infection
Hemoglobin
Platelets, which help your blood clot

You may have a CBC as part of your yearly physical exam or to check for a disease. Your doctor might give you this test if you have symptoms of a condition that affects your blood cell count.

To do a CBC, a nurse puts a needle into a vein in your arm. The needle attaches to a test tube, where the blood collects. A lab then analyzes the blood sample.

Symptoms and Causes of Anemia

Anemia can cause abnormal MCH readings on blood tests. Often a lack of iron causes anemia with a low MCH. Your body needs iron to make hemoglobin.

Pregnancy, blood loss, and weight loss surgery can all cause a drop in your iron levels and lead to iron-deficiency anemia or low hemoglobin and MCH levels.

When you have iron deficiency anemia, you may have symptoms like:

Weakness
Tiredness
Pale or yellow skin
Trouble catching your breath
Dizziness
Fast or abnormal heartbeat
Chest pain
Headache
Cold hands or feet

An anemia with a high MCH level could also be a sign that you don’t have enough vitamin B12 or other nutrients. Your body needs vitamin B12 to make healthy blood cells, nerves, and DNA.

Signs of low vitamin B12 include:

Numbness or tingling in your hands and feet
Trouble walking or staying balanced
Trouble thinking
Tiredness
Weakness
Swollen tongue

An anemia with a high MCH is called macrocytic anemia. When you have this condition, your red blood cells are larger than normal.

Other causes of macrocytic anemia include:

Lack of enough folic acid
Liver disease
Alcohol misuse
Underactive thyroid gland
Certain medicines that treat cancer, diabetes, seizures, and autoimmune diseases
Myelodysplastic syndrome, a type of bone marrow cancer

Treatment of Anemia With a Low or High MCH

Which treatment you need depends on the condition that raised or lowered your MCH level.

If you have anemia, supplements can replace what your body lacks. You may also need treatment for the condition that caused your anemia. For example, if the cause is blood loss, birth control pills lessen heavy bleeding during periods. If you have a bleeding polyp or tumor, you may need surgery to remove it.

If your body doesn’t have enough vitamin B12 or folate, your treatment will be to get more of these vitamins. They’re in foods like fish, liver, green leafy vegetables, and fortified cereals. If you’re a vegetarian or you don’t eat enough foods that have vitamin B12, you can take supplements or get regular B12 shots from your doctor.

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American Society of Hematology: “Anemia.”

Case Reports in Neurological Medicine: “Reversible vitamin B12 deficiency presenting with acute dementia, paraparesis, and normal hemoglobin.”

Harvard Medical School: “The A list of B12 foods,” “Vitamin B12 deficiency can be sneaky, harmful.”

Indian Journal of Hematology & Blood Transfusion: “Evaluation of macrocytosis in routine hemograms.”

Mayo Clinic: “Anemia,” “Complete Blood Count (CBC),” “Iron deficiency anemia,” “Macrocytosis: What Causes It?”

Medscape: “Mean Corpuscular Hemoglobin (MCH) and Mean Corpuscular Hemoglobin Concentration (MCHC).”

National Heart, Lung, and Blood Institute: “Blood Tests.”

NHS: “Symptoms: Vitamin B12 or folate deficiency anemia.”

Sarma, P. Clinical Methods: The History, Physical, and Laboratory, Butterworths, 1990.

University of Rochester: “What Are Red Blood Cells?”

MCH levels in blood tests: What do they mean?

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Doctors regularly order blood tests to get an idea of the overall health of their patients. One of the things they check for is levels of MCH, or mean corpuscular hemoglobin.

These levels are regularly used to help diagnose blood disorders but can be difficult to understand. Different MCH levels may cause a variety of symptoms, which will require individual treatments.

MCH stands for mean corpuscular hemoglobin.

MCH levels refer to the average amount of hemoglobin found in the red blood cells in the body. Hemoglobin is a protein in the blood that allows red blood cells to deliver oxygen to the cells and tissues in the body.

Though they are very similar, MCH levels should not be confused with MCHC levels.

MCH levels are the average amount of hemoglobin that is in each red blood cell. MCHC levels are the average weight of that hemoglobin based on the volume of red blood cells. Both are a reflection of the health of the hemoglobin in the blood.

A complete blood count test, or simply CBC test, is designed to give doctors a general overview of a person’s health. The test can help screen people for a variety of issues at once and may help diagnose conditions, such as bleeding disorders, infections, and anemia.

Regular health screenings will often include a CBC test. If the results come back normal, the person may not need another test until their next health screening. Doctors may order CBC tests if a person shows signs of any disorder that can affect the blood.

A CBC test can also be used to help monitor individuals who have blood disorders. Doctors will use them to track the progress of a treatment and determine how effective it is.

CBC tests examine all three types of cells in the blood. The test will give a total white, red, and platelet cell count.

CBC tests examine all three types of cells in the blood and will show the total number of white cells, red cells, and platelets in the blood.

MCH levels

Doctors will often order a CBC test to find out a person’s MCH levels. Normal MCH levels are around 27 to 33 picograms (pg) per cell in adults. These numbers may vary based on the machine used to carry out the test.

The numbers are different in young children. A person with a low MCH has concentrations at or below 26 pg per cell. A person with high MCH levels will have concentrations at 34 pg per cell or more.

Different types of anemia can cause low MCH levels. For example, microcytic anemia occurs when the blood cells are too small and cannot take in as much hemoglobin as they should. This can be due to malnutrition or nutritional deficiencies.

Some medical conditions can also cause anemia, even if the person eats a balanced and healthful diet.

Low amounts of iron in the blood can also cause low MCH levels. The body uses iron to make hemoglobin. If the body runs out of iron, iron deficiency anemia can cause low MCH levels. This type of anemia may be more common in vegetarians or people with poor nutritional intake.

People with other conditions may also experience low MCH levels. Celiac disease can prevent the body from properly absorbing iron, which makes it very difficult to keep the iron levels where they need to be.

Likewise, people who have had types of gastric surgery may also not be able to absorb iron as well as they need to. Women with excessive menstruation may also become anemic, as they lose more iron in the menstrual blood than they can recover.

Low MCH levels can also appear in a body that is lacking key vitamins. People who do not get enough B vitamins such as folate and B12 may show low MCH concentrations on their tests. Because a lack of vitamins can also show high MCH levels, doctors may request further lab testing and interpretation to make a definitive diagnosis.

Symptoms of low MCH levels

Share on Pinterest A loss of regular stamina and tiredness may be symptoms of low MCH levels.

At first, many people with low MCH levels do not experience symptoms at all. When low MCH numbers persist or fall too low, symptoms start to appear. Symptoms of low MCH include:

shortness of breath
loss of regular stamina
consistent tiredness
dizziness
weakness in the body

Low MCH numbers can also affect the skin. The skin may become pale or bruise very easily in someone with low MCH levels.

Symptoms of high MCH levels

People experiencing a high MCH caused by macrocytic anemia may experience symptoms that follow a particular pattern. People may not notice symptoms at first, but they can gradually get worse over time. Symptoms of high MCH include:

tiredness
very pale skin
fast heartbeat
nails that are brittle and easily broken
brain fog or poor concentration
confusion and memory loss

People with macrocytic anemia may also experience digestive issues. They may not have an appetite, lose weight, and have regular diarrhea. A person experiencing any of these symptoms should talk to their doctor as soon as possible.

Share on Pinterest Changes to a diet, including adding iron-rich leafy green vegetables, may help to increase MCH levels.

How doctors treat unbalanced MCH levels can vary with every case. Treatment largely depends on treating the cause of the imbalance.

Adding more vitamin B12 and folic acid to the diet can be a good way to address high MCH levels. It is best to get these from a varied and balanced diet, but supplements may also help keep these levels where they need to be.

Low MCH levels usually occur as a result of iron deficiency that has led to anemia. Doctors may recommend that individuals add more iron and vitamin B6 to their diet. Eating vitamin C and fiber, along with foods that contain iron, may also help increase the MCH levels.

Supplements for various vitamins are available to purchase online, including vitamin B12, vitamin C, folic acid, and iron. People with an imbalance in their MCH levels should always discuss a treatment plan with their doctors before taking any supplement or making drastic changes to their diet.

Most people can improve their MCH levels by making changes to their diet. Iron injections may be necessary for people with disorders that prevent iron absorption. Other people may require regular transfusions with iron-rich blood.

People should be open with their doctor about what they eat and drink during the testing process to make diagnosis and treatment as smooth as possible.

Last medically reviewed on January 27, 2020

Blood / Hematology
Medical Devices / Diagnostics
Nutrition / Diet

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MCH levels in blood tests: What do they mean

What Are MCH Levels?

Getting a CBC

Symptoms and Causes of Anemia