Anemia Health Article

Definition

Anemia is a condition characterized by abnormally low levels of healthy red blood cells or hemoglobin.

Description

The tissues of the human body need a regular supply of oxygen to stay healthy. Red blood cells, which contain hemoglobin that allows them to deliver oxygen throughout the body, live for only about 120 days. When they die, the iron they contain is returned to the bone marrow and used to create new red blood cells. Anemia can develop when heavy bleeding causes significant iron loss. It also occurs when something happens to slow down the production of red blood cells or to increase the rate at which they are destroyed.

Anemia can be mild, moderate, or severe enough to lead to life-threatening complications. Over 400 different types of anemia have been identified. Many of them are rare. More common anemia types include:

• iron deficiency anemia
• folic acid deficiency anemia
• vitamin B₁₂ deficiency anemia
• vitamin C deficiency anemia
• autoimmune hemolytic anemia
• hemolytic anemia
• sickle cell anemia
• aplastic anemia
• anemia of chronic disease

Causes & symptoms

Anemia is caused by bleeding, decreased red blood cell production, or increased red blood cell destruction. Poor diet can contribute to vitamin deficiency and iron deficiency anemia, in which fewer red blood cells are produced. Hereditary disorders and certain diseases can cause increased blood cell destruction. However, excessive bleeding is the most common cause of anemia, and the speed with which blood loss occurs has a significant effect on the severity of symptoms. Chronic blood loss may be caused by:

• heavy menstrual flow
• hemorrhoids
• nosebleeds
• cancer
• gastrointestinal tumors
• diverticulosis
• polyposis
• stomach ulcers
• long-term alcohol abuse

Acute blood loss is usually the result of:

• childbirth
• injury
• ruptured blood vessel
• surgery

Iron deficiency anemia

Iron deficiency anemia is the most common form of anemia in the world. In the United States, iron deficiency anemia affects about 240,000 toddlers between one and two years of age and 3.3 million women of childbearing age. This condition is less common in older children and in adults over 50, and it rarely occurs in teenage boys and young men.

The onset of iron deficiency anemia is gradual. The deficiency begins when the body loses more iron than it gains from food and other sources. Because depleted iron stores cannot meet the red blood cells' needs, fewer red blood cells develop. In this early stage of anemia, the red blood cells look normal, but they are reduced in number. Then the body tries to compensate for the iron deficiency by producing more red blood cells, which are characteristically small in size.

Weakness, fatigue, and a run-down feeling may be signs of mild anemia. Other signs include skin that is pasty or sallow, or lack of color in the creases of the palm, gums, nail beds, or lining of the eyelids. Someone who is weak, tires easily, is often out of breath, and feels faint or dizzy may be severely anemic. Other symptoms of anemia are:

• angina pectoris (chest pain)
• headache
• inability to concentrate and/or memory loss
• inflammation of the mouth (stomatitis) or tongue (glossitis)
• insomnia
• irregular heartbeat
• loss of appetite
• nails that are dry, brittle, or ridged
• rapid breathing
• sores in the mouth, throat, or rectum
• sweating
• swelling of the hands and feet
• thirst
• tinnitus (ringing in the ears)
• unexplained bleeding or bruising
• pica (a craving to chew ice, paint, or dirt)

Folic acid deficiency anemia

Folic acid deficiency anemia is the most common type of megaloblastic anemia, in which red blood cells are bigger than normal. It is caused by a deficiency of folic acid, a vitamin that the body needs to produce normal cells.

Folic acid anemia is especially common in infants and teenagers. Although this condition usually results from a dietary deficiency, it is sometimes due to an inability to absorb enough folic acid from foods such as:

• eggs
• fish
• green vegetables
• meat
• milk and cheese
• mushrooms
• yeast

Smoking raises the risk of developing this condition by interfering with the absorption of vitamin C, which the body needs to absorb folic acid. Folic acid anemia can be a complication of pregnancy, when a woman's body needs eight times more folic acid than it does otherwise.

Vitamin B12 deficiency anemia

A life-long regimen of B₁₂ shots is necessary to control symptoms of pernicious anemia. The patient may be advised to limit physical activity until treatment restores strength and balance.

Vitamin C deficiency anemia

A rare disorder that causes the bone marrow to manufacture abnormally small red blood cells, vitamin C deficiency anemia results from a severe, long-standing dietary deficiency.

Hemolytic anemia

Acquired hemolytic anemia can generally be cured when the cause is removed.