Signs and symptoms of vitamin deficiency anemia include:

• Fatigue
• Shortness of breath
• Dizziness
• 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 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 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. 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.

A number of factors can affect your body's vitamin stores.

In general, your risk of vitamin deficiency is increased if:

• Your diet contains little to no natural vitamin food sources, such as meat, dairy, fruits and vegetables. Vegetarians who don't eat dairy products and vegans, who don't eat any foods from animals, may fall into this category. Consistently overcooking your food also can cause vitamin deficiency.
• You're pregnant, and you aren't taking a multivitamin. Folic acid supplements are especially important during pregnancy.
• You have intestinal problems or other medical conditions that interfere with absorption of vitamins. Abnormal bacterial growth in your stomach or surgery to your intestines or stomach can interfere with the absorption of vitamin B-12.
• You abuse alcohol. Alcohol interferes with the absorption of folate and vitamin C, as well as other vitamins.
• You take certain prescription medications that can block absorption of vitamins. Anti-seizure drugs can block the absorption of folate. Antacids and some drugs used to treat type 2 diabetes may interfere with B-12 absorption.

Some risk factors are unique to specific vitamin deficiencies.

Folate-deficiency anemia risk factors include:

• Undergoing hemodialysis for kidney failure. Ask your doctor whether you need supplemental folic acid to prevent a deficiency.
• Cancer treatment. Some drugs used to treat cancer can interfere with the metabolism of folate.

Vitamin B-12 deficiency anemia risk factors include:

• Lack of 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.
• An 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 risk factors include:

• Smoking. Smoking can lead to vitamin C deficiency because it decreases the absorption of this vitamin.
• Chronic illness. Certain chronic illnesses, such as cancer or chronic kidney disease, increase your risk of vitamin C 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.