MCV Blood Test

Mean corpuscular volume, or MCV, measures the average size of your red blood cells. Red blood cells carry oxygen to every part of your body. When these cells are too big or too small, it means something is interfering with how your body makes them. Normal MCV ranges from about 80 to 100 femtoliters. A femtoliter is a tiny unit of measurement.

MCV is tested as part of a complete blood count, also called a CBC. Doctors use MCV to figure out what type of anemia you might have. High MCV means your red blood cells are larger than normal. Low MCV means they are smaller than normal. Both can affect how well oxygen reaches your tissues.

• Identify the specific type of anemia affecting your body
• Find out if you have vitamin B12 or folate deficiencies
• Check for iron deficiency, the most common cause of low MCV
• Understand why you feel tired, weak, or short of breath
• Monitor how well nutritional changes or supplements are working
• Catch red blood cell problems early, before symptoms become severe
• Evaluate if medications or alcohol use are affecting your blood cells

High MCV symptoms include fatigue, weakness, shortness of breath, and pale or yellowish skin. You might have trouble concentrating or remembering things. Tingling or numbness in your hands and feet is common, especially with vitamin B12 deficiency. Some people feel dizzy, have balance problems, or notice mood changes. A sore or swollen tongue can also occur.

Low MCV symptoms include persistent tiredness, weakness, and dizziness. Your hands and feet might feel cold. You may have brittle nails, frequent headaches, or pale skin. Your heartbeat might feel rapid or irregular. Some people crave non-food items like ice or dirt, a condition called pica. In children, low MCV can affect growth and development.

High MCV is often caused by vitamin B12 or folate deficiency. These nutrients are essential for making healthy red blood cells. Heavy alcohol use raises MCV because alcohol interferes with how your body uses these vitamins. Some medications like methotrexate or anticonvulsants can increase MCV. Hypothyroidism, or low thyroid function, also raises MCV. Poor gut health can prevent your body from absorbing B12 and folate properly.

Low MCV is most often caused by iron deficiency. Your body needs iron to make hemoglobin, the protein that carries oxygen in red blood cells. Heavy menstrual periods, poor diet, and gut problems can all lead to low iron. Chronic inflammation from conditions like autoimmune disease can lower MCV. Low stomach acid makes it harder to absorb iron from food. Certain genetic conditions like thalassemia also cause small red blood cells.

• Eat foods rich in vitamin B12 like eggs, dairy, meat, and fortified cereals if MCV is high
• Include folate-rich foods like leafy greens, beans, and citrus fruits in your diet
• Add iron-rich foods like red meat, poultry, fish, and lentils if MCV is low
• Pair iron foods with vitamin C sources like oranges or peppers to boost absorption
• Limit alcohol consumption to no more than one drink per day for women or two for men
• Support gut health with fermented foods, fiber, and probiotics to improve nutrient absorption
• Talk to your doctor about medications that might be affecting your red blood cell size
• Get your thyroid checked if you have high MCV and other thyroid symptoms
• Cook in cast iron pans to add small amounts of iron to your meals
• Consider B12 injections or sublingual supplements if you have absorption problems