HEART & BLOOD Anemia • Anemia • Aplastic anemia • Iron deficiency anemia • Sickle cell anemia • Vitamin deficiency anemia

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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 anemia — a condition in which your blood is low on healthy red blood cells.

Red blood cells carry oxygen from your lungs to all parts of your body. Without enough healthy red blood cells, your body can't get the oxygen it needs to feel energized. To produce red blood cells, your body needs iron and certain vitamins.

Vitamin deficiencies also can lead to health problems other than anemia. Fortunately, you can usually correct vitamin deficiencies with supplements and dietary changes.

Anemia occurs in many types, but the main symptom of most anemias is fatigue. That's true for vitamin deficiency anemias, which can also result in:

• Pale skin
• Sore mouth and tongue
• Shortness of breath
• Loss of appetite
• Diarrhea
• Numbness or tingling in your hands and feet

In addition, vitamin B-12 deficiency can also result in:

• Muscle weakness
• Loss of balance
• Yellow-blue colorblindness
• Mental confusion or forgetfulness

Vitamin deficiencies usually develop slowly, over several months to years. Signs and symptoms may be subtle at first, but they increase as the deficiency worsens.

Blood consists of liquid called plasma and three types of blood cells:

• White blood cells. These blood cells fight infection.
• Platelets. These blood cells help your blood clot.
• Red blood cells (erythrocytes). These blood cells carry oxygen from your lungs, by way of your bloodstream, to your brain and the other organs and tissues. Your body needs a supply of oxygenated blood to function. Oxygenated blood helps give your body its energy and your skin a healthy glow.

All three types of blood cells are produced regularly in your bone marrow — a red, spongy material located within the cavities of many of your large bones. To produce adequate numbers of healthy blood cells, especially red blood cells, your bone marrow needs a steady supply of iron, vitamin B-12, folate and vitamin C from your diet.

You need iron because red blood cells contain hemoglobin — an iron-rich substance that enables them to carry oxygen. Vitamin B-12 and folate are necessary because they're building blocks of red blood cells. Vitamin C aids in the formation of red blood cells by helping you absorb iron.

A shortage of healthy red cells
With a shortage of iron, your bone marrow produces fewer and smaller red blood cells. Anemia caused by a lack of vitamin C causes the bone marrow to make smaller red blood cells. Without enough vitamin B-12 or folate, your bone marrow produces large and underdeveloped red blood cells called megalocytes. The result is a shortage of healthy red blood cells — anemia.

Anemia caused by a lack of iron is called iron deficiency anemia. 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 also can 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 their 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. Your body stores some folate, but anemia can develop within months if your body's reserves are depleted.
• 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. Most often, 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 the 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 broken down from food in your stomach. Intrinsic factor is a protein secreted by the stomach that joins with vitamin B-12 in the stomach and then escorts it through the small intestine to be absorbed into your bloodstream. Without intrinsic factor, vitamin B-12 can't be absorbed and leaves the 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 intrinsic factor. Or it may be due to a genetic defect that suddenly halts production of the protein in your adult years. 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 you develop signs of a deficiency.
• Vitamin C deficiency anemia. A lack of vitamin C in your diet can cause this type of 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.

Certain drugs to treat cancer also can 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 also are at risk.
• You abuse alcohol, because alcohol interferes with the absorption of folate.
• You take certain prescription medications, such as some anti-seizure drugs, which can block absorption of folate.
• You're undergoing hemodialysis for kidney disease. Ask your doctor whether you need supplemental folic acid to prevent a deficiency.
• You smoke. Smoking can lead to folate deficiency because it decreases the absorption of folate.
• Your diet is poor. If your diet is greatly lacking in fresh fruits and vegetables, or you consistently overcook your food, you also may be at risk of this condition.

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 necessary for the absorption of vitamin B-12. Lack of intrinsic factor may be due to an autoimmune reaction or a genetic defect. The problem usually develops later in life and is more common in people of Scandinavian and Northern European descent.
• You have another autoimmune disorder. People with endocrine-related autoimmune disorders, such as diabetes or thyroid disease, also may be at greater risk of developing pernicious anemia.

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

• You're malnourished.
• You have another health condition such as hyperthyroidism, AIDS or cancer, which can drain the body of vitamin C and lead to a deficiency.

Doctors diagnose vitamin deficiency anemias through blood tests.

These include tests that measure 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.

Blood tests also include a check of 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. In the majority of cases, vitamin B-12 deficiency is due to a lack of intrinsic factor — a protein secreted by the stomach necessary for the absorption of vitamin B-12. The presence of antibodies to intrinsic factor 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 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.

To diagnose vitamin deficiency anemias, your doctor may also take a sample of your bone marrow. Using a needle, your doctor removes a sample of bone marrow from your hipbone. The sample is examined under a microscope to rule out other blood disorders with similar signs and symptoms.

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

• Birth defects. Lack of folate in pregnant women can lead to birth defects of the brain and spinal cord. During pregnancy, the fetus needs supplemental folic acid to make healthy blood and nerve cells.
• 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, known as peripheral neuropathy. It can lead to mental confusion and forgetfulness, because vitamin B-12 is also 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.

Vitamin deficiency anemias are treated with 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 almost all cases, folic acid supplements are taken orally every day. It usually takes a month or longer to correct folate deficiency anemia. If you're someone who 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 along with vitamin B-12 supplementation, under a doctor's supervision. If your body can't absorb vitamin B-12, you'll need lifelong injections of vitamin B-12. At first you'll need the shots, which you can administer yourself, daily. Eventually, you need them 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 during pregnancy and while breast-feeding.

Foods rich in folate include citrus fruits and juices and dark green leafy vegetables. Some breakfast cereals and enriched grain products are fortified with folic acid. Vitamin B-12 is abundant in red and white meats, and in dairy products. Vitamin C is plentiful in citrus fruits and juices, tomatoes, green peppers, cantaloupe and potatoes.

Most adults need these daily amounts of the following vitamins:

• Vitamin B12, 2.4 micrograms (mcg)
• Folate or folic acid, 400 mcg
• Vitamin C, 75 to 90 milligrams

A balanced diet provides these amounts. Ask your doctor whether you need a vitamin supplement.

Because pernicious anemia can be hereditary, let your doctor know if you have a relative with the disorder so that he or she can test your blood every few years. 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 folate and 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. Also, because alcohol can contribute to vitamin deficiency anemia, it's a good idea to limit your alcohol intake. It's recommended that men have no more than two drinks a day, and that women limit alcohol intake to one drink daily.