Definition

Iron-deficiency anemia results from reduced iron stores in the blood. This happens when there is not enough dietary iron to replace the iron used to produce hemoglobin. Hemoglobin is the component of red blood cells that carries oxygen to tissue and muscles. Excess bleeding is a common cause of anemia since it increases the need for iron replacement from the diet.

	Red Blood Cells
	Copyright © 2005 Nucleus Communications, Inc. All rights reserved. www.nucleusinc.com

Causes

Factors that play a role in causing the condition include:

• Iron that is poorly absorbed in the digestive tract (may occur due to certain intestinal diseases or after surgery)
• Chronic bleeding, including heavy menstrual bleeding or GI tract bleeding
• Inadequate iron in the diet—a common cause in infants, children, and pregnant women

Risk Factors

A risk factor is something that increases your chance of getting a disease or condition.

Risk factors for iron-deficiency anemia include:

• Rapid growth cycles (infancy, adolescence)
• Heavy menstrual bleeding or chronic blood loss from the GI tract
• Pregnancy
• Diets that contain insufficient iron (fairly rare in the United States)
• Breastfed infants who have not started on solid food after six months of age
• Babies who are given cow’s milk to drink prior to age 12 months
• Alcoholism

Symptoms

While most people with mild anemia have no symptoms, when present, symptoms may include:

• Fatigue
• Increased skin pallor
• Fingernail changes
• Weakness
• Headache
• Decreased work capacity
• Heart palpitations
• Infection
• Craving to eat things that are not food (called a pica), such as ice or clay
• Hair loss
• Shortness of breath during or after physical activity

Diagnosis

The doctor will ask about your symptoms and medical history, and perform a physical exam.

Tests may include:

• Serum iron
• Transferrin iron binding capacity
• Serum ferritin level
• Microscope examination of a blood smear
• Fecal occult blood test—to look for hidden blood in the stool

Treatment

Treatments may include:

Iron Supplements

Iron can be taken as an individual supplement or as part of a multivitamin. Iron comes in many "salt" forms. Ferrous salts are better absorbed than ferric salts. Ferrous sulfate is the cheapest and most commonly used iron salt. Some products contain vitamin C to improve iron absorption. Sustained-release or enteric-coated products may cause less stomach irritation than other products, but may be poorly absorbed.

Iron-fortified Cereal

If your healthcare provider suspects that your breastfed infant may be iron deficient, he or she may recommend that you add iron-fortified infant cereal to the baby's diet.

Prevention

A diet rich in iron can help prevent iron-deficiency anemia.

Iron in Food

The best sources of iron are liver, kidney, and red meats (heme iron). The iron from vegetable sources (nonheme iron) is less well-absorbed than iron from animal foods. However, leafy greens such as spinach and kale are good vegetable sources. Lean meat, fish, or poultry eaten with beans or dark leafy greens can improve absorption of nonheme iron by a factor of three. Foods rich in vitamin C, such as citrus fruits and juices, increase iron absorption as does cooking foods in iron utensils.

Iron Availability of Foods

Some foods decrease iron absorption. Commercial black or pekoe teas contain substances that bind to iron so it cannot be used by the body. The amount of absorbable iron in a food is more important than the total iron content.

Iron for Infants

Full-term infants who are exclusively breastfed do not need supplemental iron until they are six months old. After six months old, breastfed infants should receive extra iron in the form of iron-fortified infant cereals. These infants should have an iron-fortified infant formula after they have been weaned from breast milk.

Term infants who are not breastfed are usually given an iron-fortified infant formula from birth. After 4-6 months of age, iron-fortified infant cereals provide a good additional source of iron.

Most medical guidelines recommend that premature infants receive an iron supplement by at least eight weeks old and that it be continued until age one. Iron-fortified formula for bottle-fed infants or commercial iron drops for breastfed infants are the recommended source of supplemental iron.

RESOURCES:

American Academy of Pediatrics
http://www.aap.org

American College Obstetrics and Gynecology
http://www.acog.org

CANADIAN RESOURCES

BC Health Guide
http://www.bchealthguide.org/

Canada Health Portal
http://chp-pcs.gc.ca/CHP/index_e.jsp

References:

American Academy of Pediatrics. Committee on Nutrition. Iron fortification of infant formulas. Pediatrics. Available at: http://pediatrics.aappublications.org/cgi/content/full/104/1/119. Accessed November 15, 2004.

American Academy of Pediatrics. Committee on Nutrition. Iron fortification of infant formulas. Pediatrics. Available at: http://pediatrics.aappublications.org/cgi/content/full/104/1/119. Accessed October 30, 2006.

Beers MH, Berkow R. The Merck Manual of Diagnosis and Therapy. 17th ed. Hoboken, NJ: John Wiley & Sons; 1999.

Beers MH and Berkow R. The Merck Manual of Diagnosis and Therapy. 18th ed. Hoboken, NJ: John Wiley & Sons; 2006.

US Preventive Services Task Force. The Guide to Clinical Preventive Services: Report of the United States Preventive Services Task Force. 2nd ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2002.

US Preventive Services Task Force. The Guide to Clinical Preventive Services: Report of the United States Preventive Services Task Force. AHRQ Publication No. 06-0588; Rockville, MD: 2006.

ThirdAge WWW