Vitamin deficiency anemia is a lack of healthy red blood cells caused by lower than normal amounts of certain vitamins. Vitamins linked to vitamin deficiency anemia include folate, vitamin B-12 and vitamin C.
Vitamin deficiency anemia can occur if you don't eat enough folate, vitamin B-12 or vitamin C. Or vitamin deficiency anemia can occur if your body has trouble absorbing or processing these vitamins.
Not all anemias are caused by a vitamin deficiency. Other causes include iron deficiency and certain blood diseases. That's why it's important to have your doctor diagnose and treat your anemia. Vitamin deficiency anemia can usually be corrected with vitamin supplements and changes to your diet.
Signs and symptoms of vitamin deficiency anemia include:
- Shortness of breath
- Pale or yellowish skin
- Irregular heartbeats
- Weight loss
- Numbness or tingling in your hands and feet
- Muscle weakness
- Personality changes
- Unsteady movements
- Mental confusion or forgetfulness
Vitamin deficiencies usually develop slowly over several months to years. Vitamin deficiency symptoms may be subtle at first, but they increase as the deficiency worsens.
Vitamin deficiency anemia occurs when your body doesn't have enough of the vitamins needed to produce adequate numbers of healthy red blood cells. Red blood cells carry oxygen from your lungs throughout your body. If your diet is lacking in certain vitamins, vitamin deficiency anemia can develop. Or vitamin deficiency anemia may develop because your body can't properly absorb the nutrients from the foods you eat.
Causes of vitamin deficiency anemias, also known as megaloblastic anemias, include:
- Folate deficiency anemia. Folate, also known as vitamin B-9, is a nutrient found mainly in fruits and leafy green vegetables. A diet consistently lacking in these foods can lead to a deficiency.
An inability to absorb folate from food can also lead to a deficiency. Most nutrients from food are absorbed in your small intestine. People with diseases of the small intestine, such celiac disease, or those who have had a large part of the small intestine surgically removed or bypassed may have difficulty absorbing folate or its synthetic form, folic acid. Alcohol decreases absorption of folate, so drinking alcohol to excess may lead to a deficiency. Certain prescription drugs, such as some anti-seizure medications, can interfere with absorption of this nutrient.
Pregnant women and women who are breast-feeding have an increased demand for folate, as do people undergoing hemodialysis for kidney disease. Failure to meet this increased demand can result in a deficiency.
- Vitamin B-12 deficiency anemia (pernicious anemia). Vitamin B-12 deficiency can result from a diet lacking in vitamin B-12, which is found mainly in meat, eggs and milk. Vitamin B-12 deficiency anemia can also occur if your small intestine can't absorb vitamin B-12. This may be due to surgery to your stomach or small intestine (such as gastric bypass surgery), abnormal bacterial growth in your small intestine, or an intestinal disease, such as Crohn's disease or celiac disease, that interferes with absorption of the vitamin. Vitamin B-12 deficiency can also be caused by a tapeworm ingested from contaminated fish because the tapeworm saps nutrients from your body. However, a vitamin B-12 deficiency is most often due to a lack of a substance called intrinsic factor.
Intrinsic factor is a protein secreted by the stomach that joins vitamin B-12 in the stomach and escorts it through the small intestine to be absorbed by your bloodstream. Without intrinsic factor, vitamin B-12 can't be absorbed and leaves your body as waste. Lack of intrinsic factor may be due to an autoimmune reaction in which your immune system mistakenly attacks the stomach cells that produce it. Vitamin B-12 deficiency anemia caused by a lack of intrinsic factor is called pernicious anemia.
- Vitamin C deficiency anemia. Vitamin C deficiency can develop if you don't get enough vitamin C from the foods you eat. Vitamin C deficiency is also possible if something impairs your ability to absorb vitamin C from food. For instance, smoking impairs your body's ability to absorb vitamin C.
Risk factors for vitamin deficiency anemia vary by type of vitamin deficiency.
Folate deficiency anemia
Your risk of folate deficiency anemia may be increased if:
- You're pregnant, and you aren't taking a multivitamin containing folic acid.
- You have intestinal problems that interfere with absorption of folate.
- You abuse alcohol because alcohol interferes with the absorption of folate.
- You take certain prescription medications, such as some anti-seizure drugs, that can block absorption of folate.
- You're undergoing hemodialysis for kidney failure. Ask your doctor whether you need supplemental folic acid to prevent a deficiency.
- You're undergoing cancer treatment. Some drugs used to treat cancer can interfere with the metabolism of folate.
- You don't eat many fruits and vegetables. If your diet is greatly lacking in fresh fruits and vegetables, or you consistently overcook your food, you may be at risk of folate deficiency anemia.
Vitamin B-12 deficiency anemia (pernicious anemia)
Your risk of vitamin B-12 deficiency anemia may be increased if:
- You don't eat meat and dairy products, foods that contain a lot of vitamin B-12. Vegetarians who don't eat dairy products and vegans, who don't eat any foods from animals, may fall into this category.
- You have an intestinal disease or abnormal bacterial growth in your stomach or have had surgery to your intestines or stomach that interferes with the absorption of vitamin B-12.
- You lack intrinsic factor. Most people with a vitamin B-12 deficiency anemia lack intrinsic factor — a protein secreted by the stomach that is necessary for absorption of vitamin B-12. Lack of intrinsic factor may be due to an autoimmune reaction, or it may be inherited.
- You take certain medications. Antacids and some drugs used to treat type 2 diabetes may interfere with B-12 absorption.
- You have another autoimmune disorder. People with endocrine-related autoimmune disorders, such as diabetes or thyroid disease, may have an increased risk of developing a specific type of vitamin B-12 deficiency anemia called pernicious anemia.
Vitamin C deficiency anemia
Your risk of vitamin C deficiency anemia may be increased if:
- You're malnourished and you're not getting the nutrients and vitamins you need.
- You smoke. Smoking can lead to vitamin C deficiency because it decreases the absorption of this vitamin.
- You abuse alcohol. People who drink heavily don't absorb vitamin C as effectively, putting them at risk of vitamin C deficiency anemia.
- You have a chronic illness. Certain chronic illnesses, such as cancer or chronic kidney disease, increase your risk of vitamin D deficiency anemia by affecting the absorption of vitamin C.
Being deficient in vitamins increases your risk of many health problems:
- Pregnancy complications. Pregnant women with folate deficiency may be more likely to experience complications, such as premature birth. A developing fetus that doesn't get enough folate from its mother can develop birth defects of the brain and spinal cord. If you're thinking of becoming pregnant, ask your doctor whether you should consider taking folic acid supplements so that your body's stores of folate will be enough to support your baby.
- Nervous system disorders. While vitamin B-12 is important for the production of red blood cells, it's also important for a healthy nervous system. Untreated, vitamin B-12 deficiency can lead to neurological problems, such as persistent tingling in your hands and feet or problems with balance. It can lead to mental confusion and forgetfulness because vitamin B-12 is necessary for healthy brain function. Without treatment for vitamin B-12 deficiency, neurological complications can become permanent. Vitamin B-12 deficiency can cause these and other health problems before it leads to anemia.
- Scurvy. Vitamin C deficiency can lead to scurvy. Signs and symptoms of this rare disease include bleeding under the skin and around the gums.
Tests and diagnosis
Doctors diagnose vitamin deficiency anemias through blood tests that check:
- The number and appearance of red blood cells. People with anemia have fewer red blood cells than normal. In vitamin deficiency anemias related to a lack of vitamin B-12 and folate, the red blood cells appear large and underdeveloped. In advanced deficiencies, the numbers of white blood cells and platelets also might be decreased and look abnormal under a microscope.
- The amount of folate, vitamin B-12 and vitamin C in your blood. Folate and vitamin B-12 levels are measured at the same time because these deficiencies can cause similar signs and symptoms.
Additional tests for B-12 deficiency
If blood tests reveal a vitamin deficiency, your doctor may perform other tests to determine the type and cause, such as:
- Antibodies test. Your doctor may draw a sample of your blood to check for antibodies to intrinsic factor. Their presence indicates pernicious anemia.
- Methylmalonic acid test. You may undergo a blood test to measure the presence of a substance called methylmalonic acid. The level of this substance is higher in people with vitamin B-12 deficiency.
- Schilling test. In this test, you first ingest a tiny amount of radioactive vitamin B-12. Then your blood is checked to see if your body absorbed the vitamin B-12. After that, you ingest a combination of radioactive vitamin B-12 and intrinsic factor. If the radioactive B-12 is absorbed only when taken with intrinsic factor, it confirms that you lack your own intrinsic factor.
Treatments and drugs
Treatment for vitamin deficiency anemia includes supplements and changes in diet.
- Folate deficiency anemia. Treatment involves eating a healthy diet and taking folic acid supplements as prescribed by your doctor. In most cases, folic acid supplements are taken orally. Once your body's level of folate increases to normal, you may be able to stop taking the supplements. But if the cause of your folate deficiency can't be corrected, you may need to take folic acid supplements indefinitely.
- Vitamin B-12 deficiency anemia (pernicious anemia). For milder cases of vitamin B-12 deficiency, treatment may involve changes to your diet and vitamin B-12 supplements in pill form or as a nasal spray. Your doctor may suggest vitamin B-12 injections, particularly if your vitamin B-12 deficiency is severe. At first, you may receive the shots as often as every other day. Eventually, you'll need injections just once a month, which may continue for life, depending on your situation.
- Vitamin C deficiency anemia. Treatment for anemia related to vitamin C deficiency is with vitamin C tablets. Additionally, you increase your intake of foods and beverages that contain vitamin C.
Choose a healthy diet
You can prevent some forms of vitamin deficiency anemias by choosing a healthy diet that includes a variety of foods.
Foods rich in folate include:
- Dark green leafy vegetables
- Enriched grain products, such as bread, cereal, pasta and rice
- Fruits and fruit juices
Foods rich in vitamin B-12 include:
- Fortified foods, such as breakfast cereals
- Milk, cheese and yogurt
- Red and white meats and shellfish
Foods rich in vitamin C include:
- Citrus fruits and juices
- Sweet peppers
Most adults need these daily dietary amounts of the following vitamins:
- Vitamin B-12, 2.4 micrograms (mcg)
- Folate or folic acid, 400 mcg
- Vitamin C, 75 to 90 milligrams
Pregnant and breast-feeding women may require more of each vitamin.
Consider a multivitamin
If you're concerned about getting enough vitamins from the food you eat, ask your doctor whether a multivitamin may be right for you. Most people get enough vitamins from the foods they eat. But if your diet is restricted, you may wish to take a multivitamin.
Smoking interferes with the absorption of nutrients, such as vitamin C, so it can raise your risk of a vitamin deficiency. If you smoke, quit. If you don't smoke, don't start. If you've tried to quit on your own and haven't been successful, talk with your doctor about strategies to help you quit.
Drink alcohol in moderation, if at all
Alcohol can contribute to vitamin deficiency anemia. If you choose to drink alcohol, do so in moderation. For healthy adults, moderate drinking is generally considered to be:
- Two drinks a day for men age 65 and younger
- One drink a day for men older than age 65
- One drink a day for women of any age
A drink is 12 ounces (355 milliliters) of beer, 5 ounces (148 milliliters) of wine or 1.5 ounces (44 milliliters) of 80-proof distilled spirits.