Guide to Mean Corpuscular Hemoglobin Concentration (MCHC)

WRITTEN BY

The Levels Team

Updated: 05/22/2025|12 min read

Summary

Mean corpuscular hemoglobin concentration (MCHC) is a measurement of the average concentration of hemoglobin inside your red blood cells. 

Why It Matters

Hemoglobin is the iron-containing protein that gives red blood cells their color and allows them to carry oxygen throughout your body. Your body relies on hemoglobin to transport oxygen from your lungs to all your tissues. Each hemoglobin molecule can carry four oxygen molecules.

MCHC (Mean Corpuscular Hemoglobin Concentration) is an important indicator of red blood cell oxygen-carrying efficiency. It measures the average concentration of hemoglobin within red blood cells, reported as grams of hemoglobin per deciliter of red blood cells (g/dL).

While MCH (Mean Corpuscular Hemoglobin) measures the average amount of hemoglobin per red blood cell, MCHC specifically measures how densely packed that hemoglobin is inside each cell. This distinction is important:

• MCH tells you the average hemoglobin content in each red blood cell (in picograms)
• MCHC tells you the average hemoglobin concentration per red blood cell (RBC) (in g/dL)

This difference means MCHC can detect issues that MCH might miss. For example, if a red blood cell is larger than normal but contains a proportionally increased amount of hemoglobin, the MCH would be high, but the MCHC might be normal---indicating the cell has normal hemoglobin concentration despite its larger size.

When MCHC is low, it means your red blood cells are "hypochromic"---they contain less hemoglobin concentration than normal, appearing paler under a microscope and potentially reducing oxygen delivery efficiency even if your red blood cell count is normal. When MCHC is high, it suggests your red blood cells might be abnormally dense with hemoglobin ("hyperchromic") or that there are other issues affecting the measurement, such as red blood cell agglutination. 

Associated Symptoms

Abnormal MCHC symptoms typically relate to the underlying conditions causing the abnormality or to reduced oxygen delivery if hemoglobin is significantly affected.

Symptoms of low MCHC (hypochromia) may include:

• Fatigue and weakness, especially during physical activity
• Pale skin, nail beds, and mucous membranes
• Dizziness or lightheadedness
• Cold hands and feet
• Brittle nails

Symptoms of high MCHC may include:

• In hereditary spherocytosis (a cause of high MCHC): jaundice (yellowing of skin/eyes), fatigue, and sometimes enlarged spleen
• In severe cases with very high MCHC: potential symptoms of poor circulation in small blood vessels

Clinical Ranges

Lab Reference Range: 32.0-36.0 g/dL

Lifestyle Factors That Can Impact It

Factors that may increase MCHC include the following:

• Iron supplementation if previously deficient 
• Vitamin B6 supplementation if deficient
• Adequate protein intake 
• Vitamin C consumption with iron-containing foods 

Factors that may decrease MCHC include the following:

• High consumption of foods that inhibit iron absorption (tea, coffee, calcium-rich foods with meals)
• Vegetarian or vegan diet without proper supplementation
• Excessive alcohol consumption 
• Crash dieting or severe caloric restriction
• Frequent blood donations
• Hyperglycemia

Other Factors That Can Impact It

Medical Conditions

• Thalassemia traits and diseases: Lower MCHC through inherited defects in hemoglobin production despite normal iron levels
• Chronic diseases associated with inflammation, like autoimmune disease, cancer, inflammatory bowel disease, diabetes, heart failure: Can reduce MCHC as inflammation blocks iron use for hemoglobin synthesis
• Liver disease: May affect MCHC in either direction, depending on the specific condition and its effects on red blood cells
• Kidney failure: Often decreases MCHC through reduced erythropoietin production (erythropoietin stimulates red blood cell creation) and nutritional deficiencies

Medications

• Chemotherapy drugs: Can decrease MCHC through suppression of bone marrow activity (red blood cells are created in bone marrow), but can also increase MCHC
• Certain antibiotics (chloramphenicol, linezolid): Can reduce MCHC by interfering with protein synthesis needed for hemoglobin production
• Anticonvulsants such as phenytoin: Can lower MCHC through interference with folate metabolism necessary for red cell development
• Antiretroviral medications: Can increase MCHC

Testing Accuracy and Stability

MCHC testing is generally reliable. But understanding several factors that can affect your results helps ensure accurate interpretation of this important measurement.

Factors That Can Affect the Accuracy of Your Test

• Severe lipemia (excessive fat in blood) can interfere with hemoglobin measurement, leading to falsely elevated MCHC results.
• Extremely high white blood cell counts can interfere with automated measurements, potentially affecting calculated MCHC values.
• Dehydration can concentrate blood and elevate MCHC, while overhydration may slightly decrease it.

How it Relates to Other Markers

MCHC is most meaningful when interpreted alongside other red blood cell indices and measurements. These other tests might include:

• Mean corpuscular volume (MCV): This test measures the average size of red blood cells. Cell size helps uncover different causes of abnormal MCHC. 
• Mean corpuscular hemoglobin (MCH): This test measures total hemoglobin content per cell. When MCH is low but MCHC is normal, it can suggest small cells with normal hemoglobin concentration. When both are low, cells are small and hemoglobin-poor.
• Red cell distribution width (RDW): This marker indicates variation in red cell size. Elevated RDW with abnormal MCHC can suggest a developing or mixed nutritional deficiency affecting red cell production.
• Hemoglobin and hematocrit: These are overall measures of your blood's oxygen-carrying capacity. MCHC helps explain why these values might be abnormal.
• Reticulocyte count: This measures newly produced red cells. High reticulocyte count with low MCHC may suggest the body is responding to anemia but still lacks sufficient iron.
• Iron studies: Ferritin, iron, and total iron binding capacity measurements help determine if low MCHC is due to iron deficiency or another cause.

What Results May Mean in the Context of Other Markers

• Low MCHC with low MCV (microcytic, hypochromic): May indicate iron deficiency or thalassemia; cells are small and pale.
• Low MCHC with normal MCV (normocytic, hypochromic): Can suggest early iron deficiency, anemia of chronic disease, or sideroblastic anemia.
• Normal MCHC with normal MCV (normocytic, normochromic): May indicate a healthy pattern or may be seen in anemia from acute blood loss or kidney disease.
• High MCHC with normal or low MCV: May suggest hereditary spherocytosis or other conditions causing red cell dehydration.
• Low MCHC with abnormal white blood cell or platelet counts: May indicate bone marrow disorders affecting multiple cell lines.

Follow-up Considerations

If your MCHC value is abnormal, your health care provider will take this into account with your other markers from your CBC and develop a personalized approach that may include addressing underlying nutritional deficiencies, treating chronic conditions, or additional testing to determine the cause. Their approach will depend on your specific situation and the likely cause of your abnormal results. You should always speak to your doctor if you have medical questions or before making medical decisions.

Additional Testing or Monitoring Your Doctor May Consider

• Vitamin B12 and folate levels
• Hemoglobin electrophoresis (for suspected thalassemia or other hemoglobin variants)
• Kidney function tests
• Liver function tests
• Lead levels (particularly in children with unexplained low MCHC)
• Inflammatory markers (if anemia of chronic disease suspected)
• Osmotic fragility test (for suspected hereditary spherocytosis)
• Bone marrow examination (in severe or unexplained cases)

When Additional Care May be Warranted

• If significantly out of range, further work up is warranted to  figure out the root cause
• Abnormal MCHC with symptoms of anemia
• Abnormal MCHC with signs of jaundice
• Persistent abnormalities despite appropriate treatment
• Progressive decline in MCHC over multiple measurements

Bibliography