MCH · high result
High MCH: what it means, causes and what to check next
Short answer
A high MCH — more than about 33 picograms of hemoglobin per red cell — almost always travels with a high MCV, because larger cells hold more hemoglobin. The common causes are vitamin B12 or folate deficiency, alcohol, liver disease, hypothyroidism, a brisk reticulocyte response and medications such as methotrexate, hydroxyurea and some anticonvulsants. MCH is read with MCV and MCHC; the work-up is B12, folate, TSH, a liver panel, a reticulocyte count and a blood film.
Medically reviewed by Youmna DiStefano, MD · Last reviewed November 2026
What is the normal range for MCH?
- age 18+: 27 – 33 pg
Full reference table, citations and testing options: MCH biomarker page.
What are the common causes of high MCH?
- Vitamin B12 or folate deficiency — megaloblastic change; B12 deficiency is common in older adults, vegans, after bariatric surgery and on metformin or acid-suppressing drugs
- Alcohol — the most common cause of a mildly high MCV and MCH in a non-anemic adult, often with a raised GGT
- Liver disease and hypothyroidism, which change the red-cell membrane
- Reticulocytosis — young red cells are large: recovery from bleeding, hemolysis, or the first weeks of treating iron, B12 or folate deficiency
- Medications — methotrexate, hydroxyurea, azathioprine, zidovudine, valproate, phenytoin, trimethoprim-sulfamethoxazole, and metformin through B12
- Myelodysplastic syndrome, aplastic anemia and other marrow disorders — usually in older adults, often with low counts in another cell line
- Pregnancy, Down syndrome and smoking (modest rises)
- Sample artifacts — cold agglutinins, high lipids and a very high white count falsely raise the measured hemoglobin and so the MCH; a high glucose swells cells and raises MCV
What symptoms go with high MCH?
- None from the MCH itself — it is an index, not a symptom
- Fatigue, breathlessness and pallor when the underlying macrocytic anemia is significant
- Tingling or numbness in the feet and hands, unsteadiness, a sore smooth tongue and memory or mood change with B12 deficiency
- Jaundice and dark urine when hemolysis is driving the reticulocyte response
What do clinicians usually check next?
- Read it with MCV, MCHC, RDW and hemoglobin on the same CBC — high MCH with a normal MCV is usually a measurement artifact
- Vitamin B12 and folate; methylmalonic acid when B12 is borderline (200–400 pg/mL)
- TSH, a hepatic panel with GGT, and an honest alcohol history
- A reticulocyte count and a peripheral blood film — hypersegmented neutrophils point to B12 or folate; oval macrocytes and dysplasia point to the marrow
- A review of every medication, including methotrexate, hydroxyurea, anticonvulsants and metformin
- Hematology referral for an unexplained MCV above about 110 fL, a falling count in another cell line, or dysplastic cells on the film
Follow-up tests available at TestWell: TSH Test (Thyroid Stimulating Hormone) ($20.99), TSH with Reflex to Free T4 Test ($29.99), TSH + Free T4 Test ($27.99), Vitamin B12 Test ($19.99), Methylmalonic Acid Test (MMA) ($48.99), GGT Test (Gamma-Glutamyl Transferase) ($19.99).
How do you recheck MCH?
Prices are cash-pay; every order adds one $6 lab processing fee. Physician authorization is included; no insurance or referral needed.
| Test or panel | Type | Price | Fasting | Results |
|---|---|---|---|---|
| Biological Age Panel | Panel · 3 tests | $59.99 | Yes | 1–3 business days |
| General Wellness Panel | Panel · 4 tests | $49.99 | Yes | 1–3 business days |
| Blood Clotting Panel | Panel · 4 tests | $149.99 | No | 3–7 business days |
| CBC with Differential Test | Test · 15 biomarkers | $17.99 | No | 1–3 business days |
Common questions
What does high MCH mean?
Each red cell is carrying more hemoglobin than average, which nearly always means the cells are larger than average (a high MCV). The common causes are vitamin B12 or folate deficiency, alcohol, liver disease, hypothyroidism, a brisk reticulocyte response and several medications. The index itself causes nothing; the cause is what is treated.
Is high MCH the same as high MCV?
They usually rise together — bigger cells hold more hemoglobin — so the causes are the same list. MCV is the primary index; MCH adds information only when MCHC is also abnormal or when the two disagree, which usually means a sample artifact such as cold agglutinins or high lipids.
What level of MCH is high?
Above about 33 picograms on most laboratory ranges (some use 32 or 34). Mild elevations of 33–35 pg with a normal hemoglobin are most often alcohol, medication or an early B12 or folate deficiency; values above 36–38 pg with anemia point firmly to megaloblastic or marrow causes and are investigated promptly.
Can high MCH be caused by alcohol?
Yes — alcohol is the most common cause of a mildly raised MCV and MCH in an adult who is not anemic, through a direct effect on the marrow and, in heavier use, folate deficiency and liver disease. A raised GGT alongside makes it more likely. The indices normalize over two to four months of abstinence, which is one way the question is settled.
Educational content, not a diagnosis. Lab results are one input; a clinician interprets them with your history and exam.