﻿ Iron Deficiency: Learn About Causes and Symptoms

Iron and Iron Deficiency

Iron and iron deficiency facts*

*Iron deficiency facts medical author:

  • Iron deficiency is the most common nutritional deficiency and the leading cause of anemia in the United States.
  • Iron deficiency is due either to increased need for iron by the body or a decreased absorption or amount of iron taken in.
  • Signs of iron deficiency include fatigue, decreased work and school performance, slow cognitive and social development during childhood, difficulty maintaining body temperature, decreased immune function, and glossitis (an inflamed tongue).
  • Blood tests establish the diagnosis of iron deficiency.
  • Dietary changes or iron supplements are possible treatments for iron deficiency.

What is iron and why do we need it?

Iron is a mineral needed by our bodies. Iron is a part of all cells and does many things in our bodies. For example, iron (as part of the protein hemoglobin) carries oxygen from our lungs throughout our bodies. Having too little hemoglobin is called anemia. Iron also helps our muscles store and use oxygen.

Iron is a part of many enzymes and is used in many cell functions. Enzymes help our bodies digest foods and also help with many other important reactions that occur within our bodies. When our bodies don't have enough iron, many parts of our bodies are affected.

What is iron deficiency and why is it a concern?

Iron deficiency is a condition resulting from too little iron in the body. Iron deficiency is the most common nutritional deficiency and the leading cause of anemia in the United States.1

The terms anemia, iron deficiency, and iron deficiency anemia often are used interchangeably but equivalent. Iron deficiency ranges from depleted iron stores without functional or health impairment to iron deficiency with anemia, which affects the functioning of several organ systems.2

Iron deficiency is a concern because:

  • Iron deficiency can delay normal infant motor function (normal activity and movement) or mental function (normal thinking and processing skills).3,4,5,6
  • Iron deficiency anemia during pregnancy can increase risk for small or early (preterm) babies.7,8 Small or early babies are more likely to have health problems or die in the first year of life than infants who are born full term and are not small.
  • Iron deficiency can cause fatigue that impairs the ability to do physical work in adults.9,10 Iron deficiency may also affect memory or other mental function in teens.11
Medically Reviewed by a Doctor on 3/14/2014

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Iron Deficiency - Signs and Symptoms Question: What were the signs and symptoms associated with your iron deficiency?
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Iron Deficiency - Treatment Question: If you have an iron deficiency, what type of treatment or supplements do you take?
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Iron Deficiency Symptoms

What are the symptoms of iron deficiency?

Medical Author: Melissa Conrad Stöppler, MD
Medical Editor: Charles P. Davis, MD, PhD

How can you tell if you have iron deficiency?

Because the signs and symptoms of iron deficiency (also termed anemia, iron deficiency anemia, sideropenia, and hypoferremia) can be very subtle, only a blood test can tell you for sure if your iron levels are too low. Anemia, which has several definitions, including a depletion of functioning red blood cells, can result from iron deficiency as well as other causes. However, some people with iron deficiency anemia have no recognizable symptoms at all. If the iron deficiency develops over a long time, causing an anemia that develops gradually, the body can adjust to the new state and you may not feel any symptoms.

On the other hand, if iron deficiency develops suddenly (such as the result of profound blood loss) the body has less time to compensate, and you may notice symptoms of iron deficiency listed below right away.

Even when symptoms of chronic, or long-term, iron deficiency are present, the symptoms are nonspecific and could be caused by a number of different problems.