Mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) are two essential components evaluated in a complete blood count, and they go hand-in-hand when diagnosing various blood disorders and physiological conditions. When an MCV blood test is low — especially in combination with a low MCH — it means that your red blood cells are smaller than normal and contain less hemoglobin than they should. This typically reflects an underlying problem with hemoglobin production, which leads to a lower number of healthy red blood cells and can ultimately result in anemia.
While anemia might not cause immediate or severe symptoms in its early stages, it can escalate into more serious health concerns when left unmanaged. Fatigue, weakness, shortness of breath, and reduced immune function are just a few of the complications that may develop over time. Fortunately, there are effective ways to improve a low MCV blood test result and boost your red blood cell indices. Increasing your intake of iron-rich foods, along with folate and vitamins A and C, plays a critical role in supporting hemoglobin synthesis and red blood cell health.
Keep reading to learn more about what to do when your MCV blood test is low and how to support optimal red blood cell function through targeted lifestyle and dietary changes.
📅 Last Updated: April 2026 | 🩺 Medically Reviewed by: Edward Salko, D.O., Medical Director | 🧪 Lab Partner: Labcorp
What Do Low MCV and MCH Mean?
When your mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) are both lower than the normal reference range, it often suggests the presence of iron-deficiency anemia, microcytosis, or thalassemia. These values are routinely assessed as part of a complete blood count (CBC) and are often further analyzed through a peripheral blood smear to determine the appearance and functionality of your red blood cells.
The standard ranges for these values are:
MCV: 80 to 100 fL
MCH: 27 to 33 pg/cell
These reference ranges may vary slightly depending on the laboratory conducting the test. However, a consistent trend of a low MCV blood test result combined with low MCH levels generally points toward abnormalities in hemoglobin concentration or structure. Such irregularities are key indicators that red blood cell formation and function are impaired.
Hemoglobin is the protein in red blood cells responsible for carrying oxygen from the lungs to the tissues and transporting carbon dioxide back to the lungs for release. When hemoglobin is deficient or malformed, red blood cell production is disrupted, leading to a reduced erythrocyte count and poor oxygenation of tissues throughout the body.
Pro Tip: You may experience serious health complications when your red blood cells are below normal values. The good news is that you can increase your erythrocyte count by improving your diet, taking supplements, and doing other things. Learn more about how to fix low RBC count.
Causes of Low MCV and MCH
MCV and MCH, along with other RBC indices, provide information about your hemoglobin and red blood cells, as a whole. If you have both low MCH and MCV, it could indicate the following conditions.
Microcytic Anemia
People with microcytic anemia have small red blood cells that appear to be paler than they should be – a condition described as hypochromic. Due to a lack of hemoglobin, RBCs shrink in size. Microcytic anemia correlates with the other blood disorders below and inflammatory disease. Notably, it’s linked to iron deficiency.
Iron-deficiency Anemia
Low MCH and MCV may suggest low intake or malabsorption of iron – a key component in the formation of hemoglobin. Know how serious iron-deficiency anemia can get and find ways to address the condition effectively.
Did You Know? Women may experience hair loss due to insufficient iron. Unlike men, women tend to lose more iron due to their menstrual cycle. Read more about female hair loss and its connection to iron deficiency.
Thalassemia
Thalassemia is a genetic disorder wherein your body fails to produce enough hemoglobin. It is likely due to a mutated gene passed along to generations. If you have anyone in your family with thalassemia, consider having your MCV and MCH checked, primarily if the condition affects one of your parents.
How Are MCV and MCH Related in a Low MCV Blood Test?
MCV and MCH are red blood cell indices, which are references to evaluate the overall health and quality of red blood cells MCV and MCH are both red blood cell indices that provide essential information about the structure and function of erythrocytes. These values work together to assess overall red blood cell health. A low MCV blood test result, when paired with a low MCH level, suggests that the red blood cells are both smaller in size and carrying less hemoglobin than normal, reinforcing the presence of anemia or related conditions.
Red blood cell indices collectively help determine the type and severity of anemia by evaluating the size, volume, and hemoglobin content of red blood cells. These indices include the following:
Mean corpuscular volume (MCV): measures the average size of red blood cells
Mean corpuscular hemoglobin (MCH): indicates the average amount of hemoglobin per red blood cell
Mean corpuscular hemoglobin concentration (MCHC): shows the concentration of hemoglobin per volume of red blood cells
Red Cell Distribution Width (RDW): measures the variation in size and volume among red blood cells
Each of these values, especially MCV and MCH, plays a role in identifying the nature of anemia. For instance, if a patient presents with a low MCV blood test and also shows decreased MCH and MCHC, it strongly suggests impaired hemoglobin production, commonly seen in iron-deficiency anemia. MCHC should remain within the normal range of 32 to 36 (d/dL); dropping below that reinforces the diagnosis.
RDW, on the other hand, often increases when anemia is present, reflecting inconsistent red blood cell size due to disrupted production. However, a low RDW is not typically a concern. Normal RDW values range from 12% to 15% and help clarify the type of anemia when viewed alongside MCV and MCH.
Low MCV and MCH — What the Numbers Mean
| Marker | Normal Range | Low Result | What Low Typically Indicates |
|—|—|—|—|
| MCV | 80–100 fL | Below 80 fL | Microcytic red blood cells — iron deficiency, thalassemia |
| MCH | 27–33 pg | Below 27 pg | Less hemoglobin per cell — iron deficiency anemia |
| MCHC | 31.5–35.7 g/dL | Below 31.5 g/dL | Low hemoglobin concentration — confirms iron deficiency |
| RDW | 12–15% | N/A | High RDW with low MCV = mixed or active deficiency |
Low MCV and MCH — Iron Deficiency Is the Most Common Cause
Iron deficiency anemia is the most common cause of low MCV
and MCH worldwide — affecting over 1.2 billion people
globally. When iron is deficient, the body cannot produce
enough hemoglobin. Red blood cells are produced smaller
than normal (low MCV) and carry less hemoglobin than they
should (low MCH). The result is blood that is less efficient
at carrying oxygen to your tissues — producing the classic
symptoms of fatigue, weakness, cold hands and feet, pale
skin, brittle nails, and brain fog.
Who is most at risk for iron deficiency:
Women with heavy menstrual periods are the highest-risk
group. Pregnant women require significantly more iron.
Vegans and vegetarians absorb only non-heme iron from
plants — which is less bioavailable than heme iron from
meat. Athletes lose iron through sweat and foot-strike
hemolysis. Anyone with Crohn’s disease, celiac disease,
or H. pylori infection may have impaired iron absorption.
The critical distinction — iron deficiency vs iron
deficiency anemia:
You can be iron deficient without yet being anemic.
Low ferritin with normal hemoglobin means your iron
stores are depleted but your CBC may still look normal.
By the time MCV and MCH drop, iron deficiency is
typically well established. This is why testing ferritin
alongside a CBC gives a far earlier warning.
The three tests to order if your MCV and MCH are low:
Test 1 — Ferritin Blood Test: measures iron storage.
Low ferritin with low MCV/MCH confirms iron deficiency anemia.
Test 2 — Iron and TIBC Panel: measures serum iron and
total iron binding capacity. High TIBC with low iron
confirms iron deficiency.
Test 3 — CBC with Differential: confirms the MCV, MCH,
MCHC, and RDW pattern that defines the type of anemia.
Reviewed by Edward Salko, D.O., Medical Director, Personalabs
Sources: World Health Organization Iron Deficiency Anemia
Report; National Institutes of Health Office of Dietary
Supplements (2024); Labcorp Test Directory (2025).
How Can I Improve My Low MCV and MCH?
Treatment for anemia, and by extension – low MCV and MCH, usually involves adjusting your lifestyle and improving your diet. In some cases, your doctor will order additional testing to find the cause of anemia. Either way, the following steps can help normalize your MCV, MCH, and the rest of your red blood cell indices.
Consume more iron-rich foods
Including foods high in iron in your diet is simple as most of these foods already comprise many staple meals. However, the challenge may lie when switching to a vegetarian or vegan lifestyle. In this case, you’ll have to consult with your nutritionist to ensure that you get enough iron from alternatives (non-heme iron).
According to the National Institutes of Health, the average intake of dietary iron should be as follows:
- Children aged 2 to 11: 11.5 to 13.7 mg/day
- Adolescents aged 12 to19: 15.1 mg/day
- Adult men: 16.3 to 18.2 mg/day
- Adult women: 12.6 to 13.5 mg/day
Consider the following iron-rich foods as part of your diet:
- Red meat (beef, liver, pork loin, etc.)
- Poultry (chicken meat and eggs)
- Shellfish (oyster, mussels, clams)
- Green leafy vegetables (spinach and collard)
- Legumes (chickpeas, and lentils)
- Sesame and pumpkin seeds
- Black beans
- Edamame
- Dried fruits
- Iron-fortified cereals
Did You Know? There are two types of iron according to their dietary sources: heme and non-heme iron. Heme can be found solely in animal products, while non-heme are from fruits and vegetables. Research shows that over 95% of functional iron in humans is heme. So if you’re a vegan or planning to be one, you must have a supplemental plan for iron that you discuss with your nutritionist.
Get more vitamin B12 and folate in your diet
Vitamin B12 and folate (Vitamin B9) are nutrients needed to form healthy red blood cells. Hence, if you have deficiencies in these vitamins, it’s highly likely to develop low MCH and MCV.
Include the following food sources of vitamin B12 and B9 in your diet:
- Fish (salmon, tuna, and trout)
- Meat (beef, pork, and poultry)
- Leafy greens (spinach, cabbage, and kale)
- Broccoli
- Brussel sprouts
- Dairy products
- Fortified cereals
Consider taking supplements
Add supplements in your diet to compensate iron, and multivitamin deficiencies. Supplements are often recommended if you’re diagnosed with medical conditions that influence the absorption of nutrients.
Iron tablets are a standard prescription for people with anemia to speed up the normalization of your RBC count and correct abnormalities in your red blood cell indices.
However, it’s important to note that supplements without any deficiency can have side effects on your health. For example, excess intake of oral iron supplements can lead to gastrointestinal issues, increase your risk of infections, and result in iron overload or hemochromatosis. Thus, it’s best to get tested for iron-deficiency anemia first, then consult your doctor on whether you should take supplements and their dosage.
Take vitamins A and C to improve iron absorption
With enough vitamins A and C in your diet, your ability to absorb iron improves. As a result, healthcare providers may also check on any deficiencies involving these vitamins when assessing iron-deficiency anemia, as well as low RBC indices like MCV, MCH, and MCHC.
Studies have shown that vitamin C increases gastrointestinal iron absorption, but only when taken in combination with iron supplements and the right dosage. Vitamin C deficiency or scurvy can also lead to anemia. Hence, if you exhibit its symptoms, a vitamin C blood test can help with the diagnosis.
On the other hand, vitamin A and beta-carotene help in iron absorption by forming a complex with iron. This prevents antinutrients like phytates from counteracting absorption.
When preparing your diet plan for iron deficiency, consider the following rich sources of vitamins A and C.
Vitamin A and beta-carotene
- Oily fish (tuna and salmon)
- Dairy products (cheese, milk, and yogurt)
- Carrots
- Apricots
- Sweet potatoes
- Mango
- Bell peppers
Vitamin C
- Citrus fruits (oranges, grapefruit, lemon)
- Strawberries
- Potatoes
- tomatoes
- Cruciferous vegetables (broccoli, cauliflower, Brussels sprouts)
Avoid iron blockers
Certain substances could inhibit the absorption of iron. They are usually components found in plants that bond to a metal atom in a process called chelation, making the compound unavailable for absorption. Two of the most notable iron blockers or antinutrients are phytates and polyphenols, which can be found in certain foods and drinks.
Therefore, if you have MCV and MCH below the normal range, regulate the following:
- Tea
- Coffee
- Cocoa powder
- Flaxseeds
- Pine nuts
- Walnuts
What to Order After a Low MCV and MCH Result
A low MCV and MCH on your CBC is a signal — not a
diagnosis. The next step is identifying the cause.
Here’s exactly what to order:
For iron deficiency confirmation — order the Ferritin
Blood Test and Iron and TIBC Panel. Low ferritin plus
high TIBC with low MCV/MCH is the classic iron deficiency
pattern.
For thalassemia screening — if iron studies are normal
despite low MCV and MCH, thalassemia trait is the next
consideration. Discuss with your provider for hemoglobin
electrophoresis testing.
For a complete blood health baseline — the CBC with
Differential gives you MCV, MCH, MCHC, RDW, and a full
white and red blood cell breakdown in a single draw.
All available through Personalabs without a doctor’s
visit. Order online, visit any Labcorp location
nationwide, and get results in 24–48 hours.
Frequently Asked Questions: Low MCV and MCH
What does low MCV and MCH mean?
Low MCV means your red blood cells are smaller than normal — below 80 femtoliters (fL). Low MCH means each red blood cell contains less hemoglobin than normal — below 27 picograms (pg). When both are low simultaneously, it almost always indicates a problem with hemoglobin production, most commonly iron deficiency anemia. Together these values point to microcytic hypochromic anemia — small, pale red blood cells that carry less oxygen than healthy cells.
What is the most common cause of low MCV and MCH?
Iron deficiency anemia is by far the most common cause worldwide, affecting over 1.2 billion people. When iron is insufficient, the body cannot make enough hemoglobin, producing smaller red blood cells with less oxygen-carrying capacity. Other causes include thalassemia (a genetic condition), chronic disease anemia, and lead poisoning. A ferritin blood test and iron panel are the standard next steps after a low MCV and MCH result.
What symptoms come with low MCV and MCH?
Common symptoms include fatigue, weakness, shortness of breath on exertion, pale skin, cold hands and feet, brittle nails, hair loss, brain fog, headaches, and rapid heartbeat. In mild cases, there may be no symptoms at all — which is why routine CBC testing is important even when you feel well.
What is the difference between low MCV and low ferritin?
Low MCV means your red blood cells are already smaller than normal — iron deficiency is established. Low ferritin means your iron stores are depleted but your red blood cells may still look normal on a CBC. Ferritin drops first, MCV and MCH drop later. This means ferritin testing catches iron deficiency earlier than a CBC alone. If your ferritin is low but MCV is still normal, supplementation now prevents anemia from developing.
What blood tests should I order after a low MCV and MCH result?
Order a Ferritin Blood Test and Iron and TIBC Panel to confirm iron deficiency — the most common cause. If iron studies are normal, discuss thalassemia screening with your provider. A CBC with Differential is the standard baseline test that measures MCV, MCH, MCHC, and RDW together. All tests available through Personalabs without a doctor’s visit — order online, visit any Labcorp location, results in 24 to 48 hours.
How long does it take for MCV and MCH to normalize with iron supplementation?
With consistent iron supplementation and dietary changes, reticulocyte counts typically improve within 1 to 2 weeks. Hemoglobin usually normalizes within 4 to 8 weeks. MCV and MCH take longer — typically 3 to 4 months — because it takes time for a full generation of new, healthy red blood cells to replace the old microcytic ones. Retesting CBC and ferritin at 8 to 12 weeks confirms treatment is working.
The Bottom Line
If your CBC shows low MCV and MCH, you don’t need to immediately rush to the ER. However, it doesn’t mean you should ignore it as well, as it may cause symptoms that can affect your routine. Inform your doctor or a professional provider via a virtual channel about the results. Whether it’s anemia as an isolated condition or a symptom of a more complex illness, make sure you follow through with the recommended diet improvement and/or supplementation.
