Iron-Deficiency Anemia: Symptoms, Causes, And More - Healthline

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What Is Iron-Deficiency Anemia?

Medically reviewed by Abby Sikorcin, MPAS, PA-C — Written by Jacquelyn Cafasso and Rachael Zimlich, RN, BSN — Updated on September 4, 2025

Symptoms
Causes
Risk factors
Anemia in women
Diagnosis
Complications
Treatment
Prevention
Takeaway

Low iron levels can mean you have iron-deficiency anemia. It can occur for many reasons, including not consuming enough iron or experiencing blood loss.

Anemia occurs when you have a decreased level of hemoglobin in your red blood cells (RBCs). Hemoglobin is the protein in your RBCs that’s responsible for carrying oxygen to your tissues.

Iron-deficiency anemia is the most common type of anemia. It occurs when your body doesn’t have enough iron, which your body needs to make hemoglobin. When there isn’t enough iron in your blood, the rest of your body can’t get the amount of oxygen it needs.

While the condition may be common, many people don’t know they have iron-deficiency anemia. It’s possible to experience symptoms for years without knowing the cause.

In individuals of childbearing age, a common cause of iron-deficiency anemia is a loss of iron in the blood due to heavy menstruation or pregnancy. A poor diet, or certain intestinal diseases that affect how the body absorbs iron, can also cause iron-deficiency anemia.

Read on to take a closer look at the symptoms, causes, and treatment of iron deficiency anemia.

What are the symptoms of iron-deficiency anemia?

The symptoms of iron-deficiency anemia can be mild at first, and you may not even notice them. According to the American Society of Hematology (ASH), most people don’t realize they have mild anemia until they have a routine blood test.

The symptoms of moderate to severe iron-deficiency anemia can include:

general fatigue
weakness
pale skin
shortness of breath
dizziness
strange cravings to eat items with no nutritional value (pica)
a tingling or crawling feeling in the legs
tongue swelling or soreness
cold hands and feet
fast or irregular heartbeat
brittle nails
headaches

What are the causes of iron-deficiency anemia?

According to the ASH, iron deficiency is the most common cause of anemia. There are many reasons that a person might become deficient in iron. These include:

Inadequate iron intake

Eating too little iron over an extended period of time can cause a shortage in your body. Foods such as meat, eggs, and some green leafy vegetables are high in iron. Because iron is essential during times of rapid growth and development, pregnant people and young children may need even more iron-rich foods in their diet.

Pregnancy or blood loss due to menstruation

Heavy menstrual bleeding is a common cause of iron-deficiency anemia in individuals of childbearing age. So is pregnancy, because your body needs more iron during this time in order to create enough oxygen for the baby.

Internal bleeding

Certain medical conditions can cause internal bleeding, which can lead to iron-deficiency anemia. Examples include a stomach ulcer, polyps in the colon or intestines, or colon cancer. Regular use of certain pain relievers, such as aspirin, can also lead to bleeding in the stomach.

Inability to absorb iron

Certain disorders or surgeries that affect the intestines can also interfere with how your body absorbs iron. Even if you get enough iron in your diet, celiac disease or intestinal surgery such as gastric bypass may limit the amount of iron your body can absorb.

Endometriosis

If you have endometriosis, you may have heavy blood loss during menstrual periods. You may not even know you have endometriosis because it occurs hidden in the abdominal or pelvic area outside of the uterus.

Genetics

Some conditions — like celiac disease — that can make it difficult to absorb enough iron are passed down through families. There are also genetic conditions or mutations that can add to the problem. One of these is the TMPRSS6 mutation.

This mutation causes your body to make too much hepcidin. Hepcidin is a hormone that can block your intestines from absorbing iron.

Other genetic conditions may contribute to anemia by causing abnormal bleeding. Examples include Von Willebrand disease and hemophilia.

What are the risk factors of iron-deficiency anemia?

Anemia is a common condition and can occur in people of any age and from any ethnic group. Some people may be at greater risk of iron-deficiency anemia than others, including:

individuals of childbearing age
pregnant people
people with poor diets
people who donate blood frequently
infants and children, especially those born prematurely or experiencing a growth spurt
vegetarians who don’t replace meat with another iron-rich food
teenagers who have a greater need for iron in periods of rapid growth
adults over age 65
people exposed to lead in their environment or water
high-performance and endurance athletes like marathon runners

If you’re at risk of iron-deficiency anemia, talk with a doctor to determine if blood testing or dietary changes could benefit you.

Why is iron-deficiency anemia more common in women?

The use of binary terms such as “male” and “female” or “men” and “women” in this article reflects the language of the sources we’ve used. Unless otherwise noted, it’s unclear whether the research we reference included participants with expansive gender identities.

Pregnancy, significant menstrual bleeding, endometriosis, and uterine fibroids are all reasons that women are more likely to experience iron-deficiency anemia.

Heavy menstrual bleeding occurs when a woman bleeds more or longer than usual during menstruation. According to the Centers for Disease Control and Prevention (CDC), typical menstrual bleeding lasts for 4 to 5 days, and the amount of blood lost ranges from 2 to 3 tablespoons.

Individuals with excess menstrual bleeding typically bleed for more than 7 days and lose twice as much blood as those with typical menstrual bleeding.

A pelvic ultrasound can help a doctor look for the source of excess bleeding during a woman’s period, such as fibroids. Like iron-deficiency anemia, uterine fibroids often don’t cause symptoms. They occur when muscular tumors grow in the uterus.

While they’re not usually cancerous, fibroids can cause heavy menstrual bleeding that can lead to iron-deficiency anemia.

How is iron-deficiency anemia diagnosed?

A doctor can diagnose anemia with blood tests. These include:

Complete blood count (CBC) test

A complete blood count (CBC) is usually the first test a doctor will use. A CBC measures the amount of cellular or cell-related components in the blood, including:

red blood cells (RBCs)
white blood cells (WBCs)
hemoglobin
hematocrit
platelets

A CBC provides information about your blood that’s helpful in diagnosing iron-deficiency anemia. This information includes:

the hematocrit level, which is the percent of blood volume made up of RBCs
the hemoglobin level
the size of your RBCs

Normal hematocrit range	Normal hemoglobin range
Adult women	34.9 to 44.5 percent	12.0 to 15.5 grams per deciliter
Adult men	38.8 to 50 percent	13.5 to 17.5 grams per deciliter

In iron-deficiency anemia, the hematocrit and hemoglobin levels are low. Also, RBCs are usually smaller in size than normal.

A CBC test is often performed as part of a routine physical examination. It’s a good indicator of a person’s overall health. It may also be performed routinely before surgery. This test is useful for diagnosing this type of anemia because most people who have an iron deficiency don’t realize it.

Other tests

Anemia can usually be confirmed with a CBC test. Your doctor might order additional blood tests to determine how severe your anemia is and help determine treatments. They may also examine your blood through a microscope. These blood tests will provide information, including:

the iron level in your blood
your RBC size and color (RBCs are pale if they’re deficient in iron)
your ferritin level
your total iron-binding capacity (TIBC)

Ferritin is a protein that helps with iron storage in your body. Low levels of ferritin indicate low iron storage. A TIBC test is used to reflect the amount of transferrin that’s carrying iron. Transferrin is a protein that transports iron.

Certain at-home test kits can check iron levels, ferritin levels, and TIBC.

Tests for internal bleeding

If your doctor is concerned that internal bleeding is causing your anemia, additional tests may be needed. One test you may have is a fecal occult test to look for blood in your feces. Blood in your feces may indicate bleeding in your intestine.

Your doctor may also perform an endoscopy, in which they use a small camera on a flexible tube to view the linings of your gastrointestinal tract. Here are the two types:

An EGD test, also called an upper GI endoscopy, allows a doctor to examine the lining of the esophagus, stomach, and upper part of the small intestine.
A colonoscopy, also called a lower GI endoscopy, allows a doctor to examine the lining of the colon, which is the lower portion of the large intestine.

These tests can help identify sources of gastrointestinal bleeding.

»Learn more:Find a primary care doctor in your area today.

What are the health complications of iron-deficiency anemia?

Most cases of iron-deficiency anemia are mild and don’t cause complications. The condition can usually be corrected easily. However, if anemia or iron deficiency is left untreated, it can lead to other health problems. These include:

Rapid or irregular heartbeat

When you’re anemic, your heart has to pump more blood to make up for the low amount of oxygen. This can lead to an irregular heartbeat. In severe cases, it can lead to heart failure or an enlarged heart.

Pregnancy complications

In severe cases of iron deficiency, a child may be born prematurely or with a low birth weight. Most pregnant people take iron supplements as part of their prenatal care to prevent this from happening.

Delayed growth in infants and children

Infants and children who are severely deficient in iron may experience delayed growth and development and be more prone to infections.

How is iron-deficiency anemia treated?

How your iron-deficiency anemia is treated will depend on how severe the problem is and what caused it in the first place. Most forms of this condition involve a lack of iron in your diet or problems with your body absorbing the iron you do consume. Below are some options for treatment.

Iron supplements

Iron tablets can help restore iron levels in your body. If possible, you should take iron tablets on an empty stomach, which helps the body absorb them better. If they upset your stomach, you can take them with meals. You may need to take the supplements for several months. Iron supplements may cause constipation or black stools.

Diet

Diets that include the following foods can help treat or prevent iron deficiency:

red meat
dark green, leafy vegetables
dried fruits
nuts
iron-fortified cereals

Additionally, vitamin C may help your body absorb iron. If you’re taking iron tablets, a doctor might suggest taking the tablets along with a source of vitamin C, such as a glass of orange juice or citrus fruit.

You may also need to consider foods or drinks, such as black tea, that can lower your iron levels or decrease iron absorption.

Treating the underlying cause of bleeding

Iron supplements won’t help as much if excess bleeding causes the deficiency. A doctor may prescribe birth control pills to individuals who have heavy periods. This can reduce the amount of menstrual bleeding each month.

If your bleeding is caused by an injury, tear, or other internal problem, surgery could be required to stop the bleeding.

In the most severe cases, a red blood cell transfusion or intravenous iron can quickly replace iron and blood loss.

How to prevent iron-deficiency anemia

Iron-deficiency anemia, caused by inadequate iron intake, can be prevented by eating a diet high in iron-rich foods and vitamin C. Mothers should feed their babies breast milk or iron-fortified infant formula.

Foods high in iron	Foods high in vitamin C
meat, such as lamb, pork, chicken, and beefbeanspumpkin and squash seedsleafy greens, such as spinachraisins and other dried fruiteggsseafood, such as clams, sardines, shrimp, and oystersiron-fortified dry and instant cereals	fruits such as oranges, grapefruits, strawberries, kiwis, guavas, papayas, pineapples, melons, and mangoesbroccolired and green bell peppersBrussels sproutscauliflowertomatoesleafy greens

Takeaway

Iron-deficiency anemia is the most common type of anemia. It occurs when your body doesn’t have enough iron. Potential causes include not eating enough iron-rich foods, blood loss due to menstruation, and inability to absorb iron.

If you suspect you have an iron deficiency, see a doctor. They can diagnose anemia with blood tests.

Don’t try to diagnose and treat iron-deficiency anemia by yourself. You could end up with too much iron in your blood which can cause other health conditions, including constipation and even liver damage.

How we reviewed this article:

SourcesHistoryHealthline has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical journals and associations. We only use quality, credible sources to ensure content accuracy and integrity. You can learn more about how we ensure our content is accurate and current by reading our editorial policy.

About heavy menstrual bleeding. (2024).https://www.cdc.gov/female-blood-disorders/about/heavy-menstrual-bleeding.html
Anemia. (n.d.).https://www.hematology.org/education/patients/anemia
Anemia of inflammation or chronic disease. (2018).https://www.niddk.nih.gov/health-information/blood-diseases/anemia-inflammation-chronic-disease
Anemia or iron deficiency. (2025).http://www.cdc.gov/nchs/fastats/anemia.htm
Iron-deficiency anemia? (2022).https://www.nhlbi.nih.gov/health-topics/iron-deficiency-anemia
Iron-deficiency anemia. (2021).https://www.womenshealth.gov/a-z-topics/iron-deficiency-anemia

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Medically reviewed by Abby Sikorcin, MPAS, PA-C — Written by Jacquelyn Cafasso and Rachael Zimlich, RN, BSN — Updated on September 4, 2025

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