Mean Corpuscular Hemoglobin Concentration (MCHC)
Mean Corpuscular Hemoglobin Concentration (MCHC) measures how concentrated hemoglobin is within your red blood cells — how densely packed the oxygen-carrying protein is relative to cell size. While MCH tells you how much hemoglobin is in each cell, MCHC tells you the concentration. Low MCHC indicates “pale” under-filled cells (classic iron deficiency), while high MCHC suggests abnormally dense cells (hereditary spherocytosis). This helps confirm anemia type and guide treatment.
Mean Corpuscular Hemoglobin Concentration (MCHC) measures the average concentration of hemoglobin inside your red blood cells — essentially how “densely packed” the oxygen-carrying protein is within each cell. While MCH tells you how much hemoglobin is in each cell, MCHC tells you how concentrated that hemoglobin is relative to the cell’s size.
Why does this matter? MCHC is particularly useful for confirming iron deficiency anemia, where cells become “pale” (hypochromic) because hemoglobin concentration drops. It also helps identify rare conditions like hereditary spherocytosis, where cells are abnormally dense. Combined with other red blood cell indices, MCHC creates a complete picture of how well your red blood cells are built and functioning.
This measurement is part of the Complete Blood Count (CBC) and works alongside MCH, MCV, and hemoglobin to classify anemia and guide treatment. Understanding all these values together gives the clearest view of your red blood cell health.
Key Benefits of MCHC Testing
MCHC helps confirm whether red blood cells are properly filled with hemoglobin. Low values indicate “hypochromic” cells — pale, under-filled cells that can’t carry oxygen efficiently. This pattern strongly suggests iron deficiency and helps differentiate it from other causes of anemia.
High values are less common but clinically significant — they can indicate hereditary spherocytosis or other conditions causing abnormally dense cells. MCHC also serves as a quality check on lab results, as certain measurement errors produce characteristic abnormal values.
What Does MCHC Measure?
MCHC measures the average concentration of hemoglobin within red blood cells, expressed in grams per deciliter (g/dL). It accounts for cell size, unlike MCH which measures absolute hemoglobin amount.
Understanding the Measurement
The calculation: MCHC = Hemoglobin (g/dL) ÷ Hematocrit (%) × 100
Normal values typically range from about 32-36 g/dL. This represents how concentrated hemoglobin is within the red blood cell volume.
MCHC vs. MCH — Understanding the Difference
This distinction is important for accurate interpretation:
MCH: Average hemoglobin amount per cell (in picograms). Depends on both cell size and hemoglobin content.
MCHC: Average hemoglobin concentration within cells (in g/dL). Accounts for cell size — measures how “packed” the hemoglobin is.
Example: A large cell (high MCV) with normal hemoglobin amount will have high MCH but may have normal MCHC because the hemoglobin is spread through a larger volume. MCHC reveals the density; MCH reveals the absolute amount.
What the Values Mean
Low MCHC (hypochromic): Cells are “pale” — hemoglobin is less concentrated than normal. The cell has relatively less oxygen-carrying capacity per unit volume.
Normal MCHC (normochromic): Hemoglobin concentration within cells is appropriate.
High MCHC (hyperchromic): Cells are abnormally dense with hemoglobin. Rare, but significant when present.
Why This Test Matters
Confirms Iron Deficiency
Low MCHC is a hallmark of iron deficiency anemia. When iron is insufficient, cells can’t be properly filled with hemoglobin, resulting in pale, under-concentrated cells. This pattern helps confirm iron deficiency and differentiate it from other anemias.
Identifies Thalassemia
Thalassemia also causes low MCHC due to reduced hemoglobin production. The pattern of low MCHC with low MCV but relatively normal red blood cell count points toward thalassemia rather than iron deficiency.
Detects Spherocytosis
Hereditary spherocytosis causes abnormally high MCHC because red blood cells lose membrane and become dense spheres. Elevated MCHC is an important screening clue for this condition.
Quality Control Indicator
Because MCHC has a relatively narrow normal range, abnormal values sometimes indicate laboratory issues rather than true abnormalities. Very high values may suggest sample problems like lipemia (high blood fats) or hemolysis (broken cells) that need verification.
Completes the Anemia Picture
MCHC works with MCH and MCV to fully characterize red blood cells. Together, these indices reveal whether cells are the right size, contain the right amount of hemoglobin, and are properly concentrated — essential information for diagnosing anemia causes.
What Can Affect Your MCHC?
Causes of Low MCHC (Hypochromic Cells)
Iron deficiency: The classic cause. Without enough iron, hemoglobin production is limited, and cells can’t achieve normal concentration. The most common reason for low values.
Thalassemia: Inherited disorders of hemoglobin production result in under-filled cells even when iron is adequate.
Chronic disease anemia: Long-term inflammatory conditions can impair iron utilization, leading to reduced hemoglobin concentration.
Sideroblastic anemia: Rare condition where iron can’t be properly incorporated into hemoglobin.
Lead poisoning: Interferes with hemoglobin synthesis.
Causes of High MCHC (Hyperchromic Cells)
Hereditary spherocytosis: Red blood cells lose membrane and become dense spheres with concentrated hemoglobin. The most significant cause of truly elevated values.
Autoimmune hemolytic anemia: Antibodies attack red blood cells, sometimes creating spherocytes with high concentration.
Severe burns: Can cause red blood cell changes increasing concentration.
Laboratory artifact: High values often result from sample issues rather than true abnormalities. Lipemia (high blood fats), cold agglutinins, or hemolysis can falsely elevate readings.
Testing Considerations
MCHC is calculated automatically as part of the CBC. No special preparation or fasting is needed. Sample quality matters — hemolyzed or lipemic samples can produce inaccurate results. If values seem inconsistent with other findings, sample issues should be considered.
When Should You Get Tested?
Symptoms of Anemia
Fatigue, weakness, pale skin, shortness of breath, dizziness, or rapid heartbeat warrant a complete CBC including MCHC to evaluate anemia and help determine its cause.
Known or Suspected Iron Deficiency
If iron deficiency is suspected, MCHC helps confirm the diagnosis. The classic iron deficiency pattern includes low MCHC along with low MCV and low MCH.
Family History of Blood Disorders
If family members have thalassemia, spherocytosis, or other inherited blood conditions, screening with CBC provides important information. High MCHC can be an early indicator of spherocytosis.
Unexplained Jaundice or Gallstones
Hereditary spherocytosis causes increased red blood cell breakdown, leading to jaundice and gallstones. MCHC helps evaluate for this condition when these symptoms occur, especially at young ages.
Monitoring Known Conditions
If you have iron deficiency anemia, thalassemia, or other blood conditions, regular monitoring including MCHC tracks your status and treatment response.
Routine Health Screening
MCHC is included in standard CBC testing, providing baseline information about red blood cell health as part of regular checkups.
Understanding Your Results
MCHC is interpreted alongside other CBC values for the most accurate picture:
Low MCHC (below ~32 g/dL): Indicates hypochromic cells — hemoglobin concentration is reduced. Most commonly indicates iron deficiency. Also seen in thalassemia and chronic disease anemia. Check iron studies to determine cause.
Normal MCHC (32-36 g/dL): Hemoglobin is appropriately concentrated within cells. If anemia is present with normal MCHC, consider blood loss, B12/folate deficiency, or chronic disease as causes.
High MCHC (above ~36 g/dL): Unusual — cells are abnormally dense. Consider hereditary spherocytosis, autoimmune hemolytic anemia, or laboratory artifact. Often warrants repeat testing and further evaluation if confirmed.
Pattern Recognition with Other Indices
Low MCHC + Low MCV + Low MCH: Classic iron deficiency — small, pale, under-filled cells
Low MCHC + Low MCV + Normal/High RBC count: Suggests thalassemia — similar cell appearance but different cause
Normal MCHC + High MCV + High MCH: Suggests B12 or folate deficiency — large cells, normally concentrated
High MCHC + Normal or Low MCV: Suggests spherocytosis — dense, rounded cells
When High Values Need Investigation
Because truly high MCHC is uncommon, elevated values should prompt consideration of both genuine causes (spherocytosis) and laboratory artifacts. If you have high MCHC, your provider may recommend repeat testing or additional evaluation.
What to Do About MCHC Abnormal Results
For Low MCHC
Evaluate iron status: Check ferritin, serum iron, TIBC, and transferrin saturation to confirm iron deficiency.
If iron deficient: Address through diet (red meat, poultry, fish, legumes, fortified foods) and supplementation as recommended. Identify and address underlying causes of iron loss.
If iron is normal: Consider thalassemia evaluation, especially with family history or relevant ancestry. Hemoglobin electrophoresis can identify thalassemia types.
Address chronic conditions: If chronic disease anemia is the cause, managing the underlying condition is key.
For High MCHC
Confirm the result: High values may reflect sample issues. Repeat testing confirms whether elevation is real.
If confirmed elevated: Evaluation for hereditary spherocytosis is appropriate. This may include peripheral blood smear review, osmotic fragility testing, and family history assessment.
If spherocytosis confirmed: Management depends on severity — mild cases may need only monitoring, while more severe cases may require folic acid supplementation or, rarely, spleen removal.
Monitor Progress
After treatment begins, repeat CBC in 4-8 weeks. Improving MCHC indicates the underlying cause is being addressed.
Related Health Conditions
Iron Deficiency Anemia
Classic Cause of Low MCHC: Without adequate iron, cells can’t achieve normal hemoglobin concentration. One of the most common nutritional deficiencies worldwide. Learn more →
Thalassemia
Inherited Cause of Low MCHC: Genetic disorders affecting hemoglobin production. Common in Mediterranean, Middle Eastern, Asian, and African populations. Learn more →
Hereditary Spherocytosis
Cause of High MCHC: Inherited red blood cell membrane defect causing dense, spherical cells. Can cause anemia, jaundice, and gallstones. Learn more →
Chronic Disease Anemia
Inflammation-Related Anemia: Chronic inflammatory conditions alter iron metabolism, sometimes lowering MCHC. Learn more →
Why Regular Testing Matters
MCHC provides insight into how well your red blood cells are constructed. Changes over time can reveal developing iron deficiency, response to treatment, or progression of blood disorders. Regular monitoring — especially for those with known risk factors — catches changes early.
As part of the standard CBC, MCHC offers ongoing assessment of red blood cell health without requiring additional testing.
Related Biomarkers Often Tested Together
Hemoglobin — Total oxygen-carrying protein. MCHC indicates how concentrated it is within cells.
Hematocrit — Percentage of blood that is red blood cells. Used in MCHC calculation.
MCH — Hemoglobin amount per cell. Complements MCHC for complete picture.
MCV — Red blood cell size. Together with MCHC, classifies anemia type.
Ferritin — Iron stores. Essential for evaluating low MCHC.
Iron and TIBC — Iron status markers explaining low MCHC.
Reticulocyte Count — Young red blood cells. Helps assess bone marrow response.
Note: Information provided in this article is for educational purposes and doesn’t replace personalized medical advice.
Frequently Asked Questions
MCHC measures the average concentration of hemoglobin within your red blood cells — how densely packed the oxygen-carrying protein is. It’s expressed in grams per deciliter (g/dL) and accounts for cell size.
MCH measures the absolute amount of hemoglobin per cell (in picograms). MCHC measures the concentration of hemoglobin relative to cell size (in g/dL). A large cell might have high MCH but normal MCHC because the hemoglobin is spread through more volume.
Iron deficiency is the most common cause — without enough iron, cells can’t achieve normal hemoglobin concentration. Thalassemia and chronic disease anemia are other causes. Low MCHC indicates “hypochromic” or pale cells.
Truly elevated MCHC is uncommon. Hereditary spherocytosis is the main cause — cells become abnormally dense. High values can also result from laboratory artifacts like lipemia or hemolysis, so confirmation may be needed.
No fasting is required. MCHC is calculated as part of the routine Complete Blood Count.
Yes — this is called normochromic anemia. The hemoglobin concentration within cells is normal, but there may not be enough total cells or hemoglobin. This pattern suggests blood loss, B12/folate deficiency, or kidney-related anemia.
Low MCHC combined with low MCV and low MCH creates the classic iron deficiency pattern — small, pale, under-filled cells. This pattern helps confirm iron deficiency and distinguishes it from other anemia types.
As part of routine CBC: annually or as recommended. When monitoring iron deficiency treatment: every 4-8 weeks until normalized. For chronic blood conditions: as directed by your healthcare provider.
References
Key Sources:
- Buttarello M, Plebani M. Automated blood cell counts: state of the art. Am J Clin Pathol. 2008;130(1):104-116.
- Cappellini MD, Motta I. Anemia in Clinical Practice—Definition and Classification. Semin Hematol. 2015;52(4):261-269.
- Da Costa L, et al. Hereditary spherocytosis, elliptocytosis, and other red cell membrane disorders. Blood Rev. 2013;27(4):167-178.
