Iron-deficiency anemia: symptoms, causes, treatments

Felix Gussone, MD - Contributor Avatar

Reviewed by Felix Gussone, MD, Ro, 

Written by Ashley Abramson 

Felix Gussone, MD - Contributor Avatar

Reviewed by Felix Gussone, MD, Ro, 

Written by Ashley Abramson 

last updated: Aug 24, 2021

4 min read

Because your body is so complex, it needs many nutrients to function properly, including iron, a mineral found in meat, some cereals, and leafy vegetables.

Iron is one important ingredient for healthy development. But a lack of iron doesn’t only stunt your growth. It can also cause iron-deficiency anemia, a common but potentially serious condition that requires medical treatment. 


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What is iron-deficiency anemia? 

Your red blood cells carry oxygen through your bloodstream, so every tissue and organ in your body can function properly. Anemia is a condition in which people lack the healthy red blood cells they need to carry oxygen to the body’s organs. One of the most common forms of anemia is iron-deficiency anemia (DeLoughery, 2016). 

While iron is important for many bodily functions, the body—particularly your bone marrow—needs it to make hemoglobin, a protein in red blood cells that carries oxygen throughout the body. When iron levels are low, red blood cells can become hypochromic (low in hemoglobin) and microcytic (smaller than average) (Warner, 2021).

Low iron may not be noticeable, but when it’s severe enough, people can experience various symptoms. In some cases, severe iron-deficiency anemia can cause serious health conditions.

Symptoms of iron-deficiency anemia

Common symptoms of iron-deficiency anemia are similar to other types of anemia. Iron-deficiency anemia symptoms may include: 

  • Dizziness

  • Lightheadedness

  • Fatigue

  • Headaches

  • Shortness of breath

  • General malaise

  • Pica, or the desire to eat non-food substances (Auerbach, 2016)

Other symptoms of low iron levels may include fatigue, hair loss, and restless legs. (DeLoughery, 2016). People with low hemoglobin may also develop brittle nails. 

If left unmanaged, iron-deficiency anemia can cause severe complications, including (Warner, 2021): 

  • Developmental delay in children 

  • Pregnancy complications 

  • Depression 

  • Increased risk of infection 

Causes of iron-deficiency anemia

Iron-deficiency anemia generally occurs when the body can’t absorb iron or loses iron (Cappellini, 2020). This can happen for several reasons, ranging from a one-time blood loss to a chronic disease. 

Iron-deficiency anemia most commonly occurs due to blood loss from menstrual periods and gastrointestinal bleeding, including from a peptic ulcer (DeLoughery, 2016). Low hemoglobin may also stem from blood loss related to injuries or postpartum bleeding. 

Decreased iron absorption is another reason for low iron levels. It may occur due to a low dietary intake of iron. Studies find people on vegetarian and vegan diets have lower hemoglobin levels (Larpin, 2019).

Medical conditions like celiac disease can also make it hard for the body to absorb iron. It’s less common, but people sometimes develop iron-deficiency anemia in developing countries due to parasite infections (Warner, 2021). 

Risk factors for iron-deficiency anemia

Anyone of any age or background can develop low iron and anemia. But certain groups of people are at an increased risk for iron-deficiency anemia: 

  • Women: Women of reproductive age are at a higher risk for iron-deficiency anemia (Turner, 2021). Blood loss from heavy periods is one of the most common causes of iron-deficiency anemia. 

  • Pregnant women: Pregnancy brings a higher risk for iron-deficiency anemia because of increased blood volume and, as a result, lower iron concentration. Anemia of pregnancy may cause complications such as prematurity and low birth weight (Sun, 2017). 

  • Vegans and vegetarians: People who don’t eat red meat, poultry, and shellfish, which contain a high amount of iron, are at a higher risk of developing iron-deficiency anemia (Larpin, 2019).

  • Frequent blood donors: Blood donation can make someone vulnerable to iron loss, resulting in a higher risk of anemia (Warner, 2021).

  • Young children: Kids up to age five are at a higher risk for iron deficiency (Lopez, 2016).

In addition, people with pre-existing health problems like celiac disease are more likely to have an iron deficiency that results in anemia. 

Diagnosis of iron-deficiency anemia

If you’re experiencing symptoms of iron-deficiency anemia, visit your healthcare provider. 

Diagnosing iron-deficiency anemia is as simple as ordering a complete blood count (CBC). Low hemoglobin and ferritin serum levels (also called serum iron) in the blood often signal that the cause is iron deficiency rather than other medical conditions (Lopez, 2016). 

Once your provider identifies you have iron-deficiency anemia, they’ll likely ask about your family medical history and if you have any other medical conditions to pinpoint the cause of your low iron. At this point, the provider might order more blood tests or other labs to find out if you have an underlying problem, like internal bleeding or celiac disease, that’s causing your low iron levels.

Treatment of iron-deficiency anemia

With treatment, the prognosis for iron-deficiency anemia is good—anemic people can often live normal, healthy lives. In mild cases, a healthcare provider might treat iron-deficiency anemia with iron supplements (Warner, 2021). 

Severe cases of iron-deficiency anemia may require more aggressive treatments, such as intravenous iron drips or blood transfusions (Lopez, 2016).  

And if iron-deficiency anemia stems from another underlying medical problem, a healthcare provider will also focus on treating that problem. If the underlying cause isn’t addressed, anemia can come with serious complications. 

Prevention of iron-deficiency anemia

It’s not always possible to prevent anemia. Sometimes, it’s hereditary or tied to other diseases that one cannot avoid. But certain lifestyle factors can prevent anemia, such as a diet rich in iron. Monitoring diseases that can contribute to iron deficiency, such as celiac disease and heavy menstrual periods, can also prevent anemia symptoms.

In general, healthy practices like a nutritious diet and exercise can promote health and, in turn, prevent diseases that may cause or worsen iron-deficiency anemia. 

If you have symptoms of anemia or you’re curious about how to prevent it, schedule a medical appointment. Your healthcare provider can help you find ways to stay healthy for the long haul, even if you have low iron. 


If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.

How we reviewed this article

Every article on Health Guide goes through rigorous fact-checking by our team of medical reviewers. Our reviewers are trained medical professionals who ensure each article contains the most up-to-date information, and that medical details have been correctly interpreted by the writer.

Current version

August 24, 2021

Written by

Ashley Abramson

Fact checked by

Felix Gussone, MD

About the medical reviewer

Felix Gussone is a physician, health journalist and a Manager, Medical Content & Education at Ro.