Iron deficiency occurs when your body doesn’t have enough of the mineral iron.

Your body needs iron to make hemoglobin, a protein in red blood cells that enables them to carry oxygen around your body.

If your body doesn’t have enough hemoglobin, your tissues and muscles won’t get enough oxygen to be able to work effectively. This leads to a condition called anemia.

Although there are different types of anemia, iron deficiency anemia is the most common type worldwide (1).

Signs and symptoms of iron deficiency vary depending on:

  • the severity of the anemia
  • how quickly it develops
  • your age
  • your current state of health

In some cases, people experience no symptoms.

Here are a few signs and symptoms of iron deficiency, starting with the most common.

Feeling very tired is one of the most common symptoms of iron deficiency anemia. This symptom can also be common in people who just don’t have enough iron, even if they haven’t received a diagnosis of deficiency (2, 3).

This fatigue happens because your body lacks the iron it needs to make a protein called hemoglobin, which helps carry oxygen around your body.

Without enough hemoglobin, less oxygen reaches your tissues and muscles, depriving them of energy. Your heart also has to work harder to move more oxygen-rich blood around your body, which can make you tired (2).

Since tiredness is often considered a normal part of a busy, modern life, it can be difficult to diagnose iron deficiency with this symptom alone.

However, it is possible for some people with iron deficiency to experience low energy alongside weakness, irritability, or difficulty concentrating (4).

Summary

Fatigue is one of the most common symptoms of iron deficiency. This is due to less oxygen reaching body tissues, depriving them of energy.

Skin that is paler than usual and pale coloring of the inside of the lower eyelids are other common symptoms of iron deficiency (5, 6).

The hemoglobin in red blood cells gives blood its red color, so low levels during iron deficiency make the blood less red. That’s why skin can lose some of its color or warmth in people with iron deficiency.

A study in children ages 6 to 11 found that paleness associated with iron deficiency may appear all over the body or be limited to one area, such as the (7):

  • face
  • gums
  • insides of lips or lower eyelids
  • nails

This is often one of the first things doctors will look for as a sign of iron deficiency. However, it should be confirmed with a blood test (6).

Paleness is more commonly seen in moderate or severe cases of anemia (7).

If you pull your lower eyelid down, the inside layer should be a vibrant red color. If it is a very pale pink or yellow color, this may indicate that you have iron deficiency. In people with darker skin tones, this may be the only area where it is noticeable.

Summary

Skin that is paler than usual in areas such as the face, lower inner eyelids, or nails may be a sign of moderate or severe iron deficiency. This is caused by lower levels of hemoglobin, which gives blood its red color.

Hemoglobin enables your red blood cells to carry oxygen around your body.

When hemoglobin levels are low during iron deficiency, oxygen levels will also be low. This means your muscles won’t receive enough oxygen to do normal activities, such as walking (8).

As a result, your breathing rate will increase as your body tries to get more oxygen. This is why shortness of breath is a common symptom (2).

If you find yourself out of breath when doing normal, daily tasks that you used to find easy, such as walking, climbing stairs, or working out, iron deficiency could be to blame.

Summary

Shortness of breath is a symptom of iron deficiency, since low hemoglobin levels mean your body cannot effectively transport oxygen to your muscles and tissues.

Iron deficiency may cause headaches, particularly in women (5, 9).

While the link between iron deficiency and headaches is still unclear, researchers theorize there are several factors at play, including the relationship between altered dopamine function and estrogen levels. However, more research needs to be done before a conclusion can be made (10).

Although there are many causes of headaches, frequent, recurrent headaches could be a symptom of iron deficiency.

Summary

Headaches can be a symptom of iron deficiency. More research is being done to look at the connection between dopamine dysfunction, estrogen levels, and iron deficiency.

Noticeable heartbeats, also known as heart palpitations, can be another symptom of iron deficiency anemia.

The association between iron deficiency, anemia, and heart problems is still being studied, but it may be related to oxygen supply (11).

Hemoglobin is the protein in red blood cells that helps transport oxygen around the body. In iron deficiency, low levels of hemoglobin mean the heart has to work extra hard to carry oxygen.

This may lead to irregular heartbeats or the feeling that your heart is beating abnormally fast.

In extreme cases, it can lead to an enlarged heart, a heart murmur, or heart failure (12, 13).

Summary

In cases of iron deficiency, the heart has to work extra hard to transport oxygen around the body. If left untreated, this can lead to irregular or fast heartbeats and even heart murmurs, an enlarged heart, or heart failure.

Dry and damaged skin and hair can be signs of iron deficiency (14).

Iron deficiency lowers the level of hemoglobin in the blood, which may reduce the amount of oxygen available to cells that cause hair growth (15).

When skin and hair are deprived of oxygen, they can become dry and weak.

Iron deficiency is also associated with hair loss, and some research suggests it could be a cause (16, 17).

It’s completely normal for some hair to fall out during everyday washing and brushing. If you’re losing clumps or much more than normal, though, it may be related to iron deficiency.

Summary

Skin and hair may receive less oxygen from the blood during iron deficiency, causing them to become dry and damaged. In more severe cases, this may lead to hair loss.

Sometimes just looking inside or around your mouth can indicate whether you have iron deficiency anemia.

Signs include a swollen, inflamed, pale, or strangely smooth tongue (18).

Iron deficiency may also cause other symptoms around your mouth, such as (19):

  • dry mouth
  • a burning feeling in your mouth
  • sore red cracks at the corners of your mouth
  • mouth ulcers
Summary

A sore, swollen, or strangely smooth tongue can be a sign of iron deficiency anemia. Cracks on the corners of your mouth may also be a sign.

Iron deficiency has been linked to restless legs syndrome (20).

Restless legs syndrome is a strong urge to move your legs while they’re at rest. It can also cause unpleasant and strange crawling or itchy sensations in your feet and legs.

It’s usually worse at night, meaning that you may find it difficult to sleep.

The causes of restless legs syndrome are not fully understood.

However, around 25% of people with iron deficiency anemia have restless legs syndrome. The prevalence of restless legs syndrome is nine times higher in people with iron deficiency compared to the general population (21).

Summary

People with iron deficiency anemia have a higher chance of experiencing restless legs syndrome, which is a strong urge to move the legs when at rest.

A much less common symptom of iron deficiency is brittle or spoon-shaped fingernails. This condition is called koilonychia (22).

Usually, the first sign is brittle nails that chip and crack easily.

In later stages of iron deficiency, spoon-shaped nails can occur, meaning the middle of the nail dips and the edges are raised to give a rounded appearance like a spoon.

However, this is a rare side effect that occurs in only about 5% of people with iron deficiency. It’s usually seen only in severe cases of iron deficiency anemia (22).

Summary

Brittle or spoon-shaped nails can be an indicator of more severe iron deficiency anemia.

There are several other signs that your iron could be low. These tend to be less common and can be linked to many conditions other than iron deficiency.

Other signs of iron deficiency anemia include:

  • Strange cravings. A hankering for strange foods or non-food items is called pica. It usually involves cravings to eat ice, clay, dirt, chalk, or paper and could be a sign of iron deficiency. It can also occur during pregnancy (23).
  • Feelings of depression. Iron deficiency anemia may be associated with depression in adults. Pregnant women with iron deficiency may also have a higher chance of developing depression (24, 25).
  • Cold hands and feet. Iron deficiency means less oxygen is being delivered to your hands and feet. Some people may feel the cold more easily in general or have cold hands and feet (5).
  • More frequent infections. Because iron is needed for a healthy immune system, lack of it may increase your risk for infections (26).
Summary

Other more generic signs of iron deficiency may include strange food cravings, feelings of depression, cold hands and feet, and more frequent infections.

Iron deficiency can be caused by a variety of factors and can happen at almost any age. A few of the most common causes are (5):

  • inadequate iron intake due to a diet that doesn’t meet the daily nutritional needs or is heavily restricted
  • inflammatory bowel disease
  • increased iron requirements during pregnancy
  • blood loss through heavy periods or internal bleeding

Bleeding in the stomach or intestines can be a common reason for anemia in adults who are no longer menstruating. This bleeding can be caused by (27):

If you think you have an iron deficiency, consider the following steps.

Talk with a doctor

If you think you’re showing signs or symptoms of iron deficiency, you should make an appointment to see a doctor.

If your doctor confirms you have iron deficiency — typically via a blood test — it’s generally fairly easy to treat. Your doctor will likely recommend increasing your intake of iron through your diet or with iron supplements (2).

The main aim of treatment is to restore hemoglobin levels to normal and replenish iron stores.

Your doctor will develop a treatment plan that best meets your healthcare needs.

Before changing your diet or deciding on any supplements, talk with your doctor.

Eat iron-rich foods

If your doctor thinks your iron deficiency may be caused by a lack of iron in your diet, think about consuming more iron-rich foods, such as:

  • red meat, such as beef and pork, and poultry
  • dark green, leafy vegetables such as spinach and kale
  • dried fruit such as raisins and apricots
  • peas, beans, and other pulses
  • seafood
  • iron-fortified foods
  • seeds and nuts
  • organ meats

Take iron supplements if your doctor recommends them

You should take an iron supplement only if a healthcare professional confirms that you have an iron deficiency or are at risk for one and can’t meet your needs through diet alone.

Keep in mind that taking iron supplements may cause some side effects, including:

However, you can minimize these side effects by taking specific types of iron supplements that may reduce negative effects, such as iron bisglycinate chelate (28).

Talk with a doctor if you are experiencing side effects related to iron supplementation.

Help boost your iron absorption

If you want to get the most out of your iron supplement, try to avoid taking it along with antacids or milk, as these can limit iron absorption.

It’s also recommended to avoid or limit high fiber foods or foods containing caffeine when you take your supplement, as these can also interfere with absorption (29).

Summary

If you think you have an iron deficiency, talk with a doctor. They may recommend that you consume more iron-rich foods (plus vitamin C to increase your iron absorption) or possibly take iron supplements.

Talk with a doctor if you have symptoms of iron deficiency. If left untreated, it can develop into iron deficiency anemia. This could eventually result in complications, including:

Iron deficiency anemia is more common in women than in men (30).

People who are pregnant or have heavy menstrual periods have the highest risk and should talk with a doctor about being tested for iron deficiency anemia.

Take iron supplements only if your doctor prescribes them. Too much iron can damage your heart, liver, and pancreas.

Iron deficiency anemia is the most common type of anemia worldwide.

Some people have obvious symptoms, while others experience none at all. This often depends on the severity of the anemia.

Common signs and symptoms include fatigue, skin that is paler than usual, feeling short of breath, and dry and damaged hair and skin.

If you think you have symptoms of iron deficiency, talk with a doctor. Self-diagnosing is not recommended.

Most forms of iron deficiency can be treated fairly easily, usually through an iron-rich diet or iron supplements, if a doctor recommends them.

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