Your body needs vitamins — nutrients found in most foods — for many reasons, including producing healthy red blood cells. If your body is deficient in certain key vitamins, you can develop a type of anemia called vitamin deficiency anemia.

In vitamin deficiency anemia, the body doesn't make enough red blood cells. Red blood cells carry oxygen from your lungs to all parts of your body. Because vitamin deficiency anemia reduces the number of healthy red blood cells, your body can't get all the oxygen it needs to feel energized. Vitamin deficiency anemia can also lead to other health problems, such as memory difficulties and tingling in your hands and feet.

You can usually correct vitamin deficiency anemia with supplements and changes in diet.

Vitamin deficiency anemias can result in:

• Fatigue
• Pale or yellowish skin
• Sore mouth and tongue
• Weight loss
• Diarrhea
• Numbness or tingling in your hands and feet
• Muscle weakness
• Irritability
• 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.

To produce adequate numbers of healthy blood cells, especially red blood cells, your body needs a healthy diet that provides a steady supply of vitamins and other nutrients. If your diet is lacking in certain vitamins, vitamin deficiency anemia can develop. Sometimes anemia develops because your body can't properly absorb the nutrients from your diet.

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 citrus 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 as Crohn's disease or 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). Rarely, vitamin B-12 deficiency results from a diet lacking in vitamin B-12, which is found mainly in meat, eggs and milk. A shortage occurs because 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 deficiency is most often due to a lack of a substance called intrinsic factor.

  Vitamin B-12 is released from food in your stomach. 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 ultimately leads to anemia.

  If the deficiency is from a lack of intrinsic factor, it's called pernicious anemia. Pernicious means "deadly." Lack of intrinsic factor was often fatal before the availability of vitamin B-12 shots. Because vitamin B-12 is stored in large amounts in your liver, it may take several years before signs of deficiency appear.

• Vitamin C deficiency anemia. A lack of vitamin C in your diet can also cause anemia. Your body needs vitamin C, found mainly in citrus fruits, to produce healthy blood cells. Vitamin C also helps your body absorb iron, an important building block of red blood cells. Other possible causes of this type of anemia are general malnutrition, cancer, hyperthyroidism or a decrease in the ability to absorb dietary iron.

Certain drugs to treat cancer can also cause vitamin deficiencies.

Do you fall into a risk category for a vitamin deficiency anemia?

Folate deficiency anemia
You're at risk of folate deficiency anemia 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.
• Your diet is poor. 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)
You may be at risk of vitamin B-12 deficiency anemia if:

• You don't eat meat and dairy products, foods that contain a lot of vitamin B-12. Strict vegetarians may fall into this category.
• You have an intestinal disease, abnormal bacterial growth in your stomach, or surgery to your intestines or stomach that interferes with the absorption of vitamin B-12.
• You lack intrinsic factor. Most people with a diagnosis of 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 a genetic defect.
• 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 pernicious anemia.

Vitamin C deficiency anemia
You may be at risk of vitamin C deficiency anemia if:

• You're malnourished and you're not getting the nutrients and vitamins you need.
• You have a health condition such as hyperthyroidism or cancer that can drain the body of vitamin C and lead to a deficiency.
• You smoke. Smoking can lead to vitamin C deficiency because it decreases the absorption of this vitamin.

Being deficient in vitamins increases your risk of many health problems:

• Birth defects. Lack of folate in pregnant women can lead to birth defects of the brain and spinal cord.
• 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. It can lead to mental confusion and forgetfulness, because vitamin B-12 is necessary for healthy brain function. 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.

If you suspect that you have a vitamin deficiency anemia, you're likely to start by seeing your family doctor or a general practitioner. However, in some cases, you may be referred to a doctor who specializes in treating blood disorders (hematologist).

Here's some information to help you get ready for your appointment, and what to expect from your doctor.

What you can do

• Write down any symptoms you're experiencing, including any that may seem unrelated to the reason for which you scheduled the appointment.
• Write down key personal information, including any major stresses or recent life changes.
• Make a list of all medications, as well as any vitamins or supplements, that you're taking.
• Write down questions to ask your doctor.

Your time with your doctor is limited, so preparing a list of questions ahead of time will help you make the most of your time together. For vitamin deficiency anemia, some basic questions to ask your doctor include:

• What's the most likely cause of my symptoms?
• Are there other possible causes for my symptoms?
• Is my condition likely temporary or chronic?
• What treatment do you recommend?
• Are there any alternatives to the approach that you're suggesting?
• I have another health condition. How can I best manage them together?
• Are there any foods I need to add to my diet?
• Are there any brochures or other material that I can take with me? What Web sites do you recommend?

In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask questions during your appointment any time that you don't understand something.

What to expect from your doctor
Your doctor is likely to ask you a number of questions. Being ready to answer them may reserve time to go over any points you want to spend more time on. Your doctor may ask:

• When did you first begin experiencing symptoms?
• How severe are your symptoms?
• Does anything seem to improve your symptoms?
• What, if anything, appears to worsen your symptoms?
• Are you a vegetarian?
• How many servings of fruits and vegetables do you usually eat in a day?
• Do you drink alcohol? If so, how often, and how many drinks do you usually have?
• Are you a smoker?

Doctors diagnose vitamin deficiency anemias through blood tests that check:

• The level and appearance of red blood cells. In anemia, you have fewer red blood cells. In vitamin deficiency anemias, the red blood cells that you do have are large and underdeveloped. In advanced deficiencies, white blood cells and platelets also 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 often coexist.

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. Diagnosing vitamin B-12 deficiency in particular may involve more tests, 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 and urine 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. If your body doesn't absorb vitamin B-12 with or without intrinsic factor, you likely have a more general absorption problem.

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. The usual dose is 400 micrograms (mcg) daily, or 600 mcg each day for most pregnant women. If you can't absorb folate easily, you may need to take folic acid supplements for life.
• Vitamin B-12 deficiency anemia (pernicious anemia). You can treat vitamin B-12 deficiency related to a poor diet with changes in your diet and vitamin B-12 supplementation, under a doctor's supervision. If your body can't absorb vitamin B-12, you'll either need lifelong vitamin B-12 injections or nasal B-12 spray. At first you'll need the shots or nasal spray as often as every other day. Eventually you'll need injections or the nasal spray just once a month. Prompt treatment is important, because neurological complications may become permanent if the B-12 deficiency isn't corrected within several months.
• Vitamin C deficiency anemia. Treatment for this rare anemia is with vitamin C tablets. Take them as directed by your doctor. Additionally, increase your intake of foods and beverages that contain vitamin C.

You can prevent some forms of vitamin deficiency anemias by eating a balanced diet and taking a multivitamin, especially during pregnancy and while breast-feeding.

Foods rich in folate include:

• Citrus fruits and juices
• Dark green leafy vegetables
• Enriched grain products, such as cereal and bread
• Dried beans and peas

Vitamin B-12 is abundant in:

• Red and white meats and shellfish
• Eggs
• Milk, cheese, yogurt

Vitamin C is plentiful in:

• Citrus fruits and juices
• Tomatoes
• Sweet peppers
• Cantaloupe
• Broccoli

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

A balanced diet usually provides these amounts. Ask your doctor whether you need a vitamin supplement. Smokers require an additional 35 milligrams of vitamin C daily.

Because pernicious anemia can be hereditary, let your doctor know if you have a relative with the disorder. The doctor will test your blood periodically. If the tests indicate vitamin B-12 deficiency, you can start treatment before signs and symptoms of the disease appear. Early diagnosis and treatment of pernicious anemia can help you avoid complications.

These other measures may help prevent vitamin deficiency anemia:

• Don't smoke. Smoking interferes with the absorption of vital nutrients, such as vitamin C, so it can raise your risk of a deficiency. The best thing you can do for your health is to stop smoking. If you can't stop, talk with your doctor about your increased nutritional needs.
• Limit alcohol. Because alcohol can contribute to vitamin deficiency anemia, it's a good idea to limit your alcohol intake. U.S. government nutrition guidelines recommend that men have no more than two drinks a day and that women limit alcohol intake to one drink daily.