Mean corpuscular hemoglobin (MCH) is a protein that helps deliver oxygen around the body. Normal MCH levels are around 27 to 31 picograms (pg) per cell in adults.

Doctors regularly order blood tests to get an idea of the overall health of their patients. Different MCH levels may cause various symptoms, which will require individual treatments.

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MCH stands for mean corpuscular hemoglobin. MCH levels refer to the average amount of hemoglobin found in the red blood cells. 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.

Doctors will often order a complete blood count (CBC) test to find out a person’s MCH levels. Normal MCH levels are around 27 to 31 picograms (pg) per cell in adults. These numbers may vary based on the machine used for the test.

The numbers are different in young children. A person with a low MCH has concentrations at or below 27 pg per cell. A person with high MCH levels will have concentrations at 34 pg per cell or more.

MCH rangeMCH Level (pg)
lowless than 27
typical27–31
highmore than 31

What is a CBC test?

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 various issues at once and may help diagnose conditions such as bleeding disorders, infections, and anemia.

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

There are several potential causes of low MCH levels, including:

  • Iron-deficiency anemia: Iron deficiency anemia is a lack of iron in the blood due to malnutrition, problems with iron absorption, cancer, or heavy internal bleeding. Heavy menstruation and pregnancy can also cause low iron levels.
  • Microcytic anemia: In microcytic anemia, red blood cells are smaller than usual due to a lack of hemoglobin.
  • Hemoglobinopathy: This is a group of conditions that affect hemoglobin, including sickle cell anemia and thalassemia.

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:

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

High MCH scores are commonly a sign of macrocytic anemia. This condition occurs when the blood cells are too big, which can be a result of not having enough vitamin B12 or folic acid in the body.

High MCH scores may also be the result of the following:

  • liver diseases
  • an overactive thyroid gland
  • drinking alcohol regularly
  • complications from certain cancers
  • complications from an infection
  • taking too many medications containing estrogen

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
  • 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.

How doctors treat unbalanced MCH levels can vary with every case.

Diet changes

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.

Foods rich in iron include:

  • dark leafy vegetables
  • liver
  • lean red meat
  • lentils, beans, and other legumes
  • tofu

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.

Supplements

Supplements for iron and various vitamins, including vitamin B12, vitamin C, folic acid, can help to increase MCH levels when it is lacking in the diet. 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.

Learn more about iron supplements here.

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.

Here are some frequently asked questions about MCH levels.

What does it mean if MCH is low?

A person may have low MCH levels if something affects the amount of hemoglobin found in the red blood cells. This can be due to conditions such as iron deficiency anemia, microcytic anemia, and hemoglobinopathy.

What does it mean if MCH is high?

Elevated MCH levels can indicate macrocytosis, which refers to red blood cells that are larger than typical. Macrocytosis can be a sign of macrocytic anemia.

How do you treat low hemoglobin?

Treatment for low hemoglobin can depend on the cause. A doctor may recommend dietary changes and supplements alongside treating any underlying condition.

What level of MCH is concerning?

Typical MCH levels are around 27 to 31 picograms (pg) per cell in adults. Levels outside of this range can indicate an underlying condition for which a person may require treatment.

Should I worry if my MCH is low?

It is generally possible to treat causes of low MCH levels, such as anemia, by increasing the amount of iron a person gets. However, it is important to contact a doctor to receive an accurate diagnosis and suitable treatment plan.