Iron deficiency anemia: the most important questions and advice

Eisenmangelanämie: Die wichtigsten Fragen und Ratschläge

Many people are familiar with the term iron deficiency, but what actually is iron deficiency anemia and how does it come about? This is an important question, since iron deficiency is the most common deficiency disease with around 30 percent of those affected worldwide and is therefore a global health problem.

In this article, you will first learn what exactly iron deficiency anemia is. We will also answer the most frequently asked questions about the disease and give you an insight into the symptoms, causes and different forms of iron deficiency anemia. Finally, you will receive some advice and valuable information on the treatment of iron deficiency anemia.

the essentials in brief

  • Iron deficiency anemia is one of the most common deficiency diseases, affecting around 30 percent of people worldwide. This constitutes a global public health problem (1,2).
  • Iron deficiency anemia is caused by a lack of the element iron in the human body. The reasons for such a deficiency can be different. We will explain the most common triggers in more detail in the course of this article.
  • The typical symptoms of iron deficiency anemia are tiredness, a feeling of exhaustion and weakness, reduced performance and pale, rough skin as well as changes in hair and nails. In addition, dizziness, breathing problems and palpitations are among the most common signs of anemia (3).

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Definition: What is Iron Deficiency Anemia?

An undersupply of the element iron can cause anemia in the human body. This occurs due to the obstruction of the formation of the red blood pigment hemoglobin. In such a case, the cells in the body cannot be supplied with enough oxygen (2). Because the hemoglobin is responsible for binding oxygen in the blood and transporting it into the body cells.

Iron deficiency anemia occurs in the form of an advanced, severe iron deficiency when the cells and organs in the body can no longer be adequately supplied with oxygen. Anemia can develop insidiously if the intake of the mineral iron is less than the body's needs for a long time (4).

Background: What you should know about iron deficiency anemia

In this section we want to give you an overview of the most important questions and answers on the subject of iron deficiency anemia. You will then be able to assess what causes iron deficiency anemia and what characterizes it in the various stages. We also tell you which doctors you can consult if you suspect iron deficiency anemia.

How is iron deficiency anemia manifested?

Typical symptoms of iron deficiency anemia include tiredness, a general feeling of exhaustion and hair loss (5). Other common characteristics are fatigue, a feeling of weakness, and a marked drop in performance. Furthermore, dizziness, pale skin, breathing problems and palpitations are mentioned as common signs of anemia (2).

Other characteristic symptoms are increased nervousness, sensitivity to cold and increased susceptibility to headaches. These signs develop when the body is already turning to the iron found in the blood (6).

What causes iron deficiency anemia?

There are several reasons for the development of iron deficiency anemia. Basically, the deficiency can set in when either iron is lost, too little iron is supplied to the body from outside or when the iron requirement increases (e.g. in women of childbearing age, during pregnancy or even when breastfeeding).

In exceptional cases, an inhibition of the absorption of iron in the body can also be the cause (7). Iron deficiency anemia can therefore develop when the iron content in the body is lower than the iron requirement . The most common causes of iron deficiency (anemia) are summarized above all:

  • Blood and thus iron loss
  • low dietary iron intake
  • Increased iron requirement
  • disturbance of iron absorption

The two main causes of iron deficiency, which can lead to anemia, are blood loss from a woman's monthly menstrual period and blood loss from gastrointestinal bleeding (5). In the following, we will explain the various causes to you in more detail and also show you the primary risk groups for iron deficiency.

Blood and thus iron loss

Increased blood loss can lead to iron deficiency. This, in turn, can lead to iron deficiency anemia. Iron is lost, for example, with:

  1. Heavy menstrual bleeding in women of childbearing age
  2. Bleeding in the gastrointestinal tract (especially in tumors and ulcers)
  3. Accidents or operations where the patient loses a lot of blood
  4. A breakdown of the blood (e.g. in the case of immune reactions)
  5. blood donation (7)

Particular attention should be paid to prolonged internal bleeding, which can lead to iron deficiency and subsequent anemia. These are e.g. T. difficult to determine and require an examination by an expert.

Woman gives someone handkerchief

In addition to bleeding in the gastrointestinal tract, heavy menstrual bleeding is the most common cause of iron deficiency anemia in women. (Image Source: Annika Gordon / Unsplash)

Women in particular belong to the primary risk group due to the monthly menstrual bleeding. According to the Professional Association of German Internists, almost half of women of childbearing age worldwide suffer from an iron deficiency (7).

Inadequate dietary iron intake

Another cause is insufficient iron intake from food. Although this is considered a rare cause (7), there are groups of people who are more susceptible due to their diet.

This includes in particular vegetarians and vegans who do not eat meat or animal products, because iron is a questionable nutrient in vegetarian and vegan diets (8). In such a case, supplements are often used to supplement the micronutrient. A targeted selection of iron-rich foods can also be helpful (9).

In addition, infants and young children, people with eating disorders and alcoholics are also at risk of not getting enough iron from their food and developing iron deficiency anemia. These groups of people often experience an unbalanced and one-sided diet, which means that they only get an insufficient amount of iron (2).

Increased iron requirement

An increased iron requirement is also a cause for the development of iron deficiency anemia. Here we list those groups of people who have an increased iron requirement:

  • Women of childbearing potential with menstrual bleeding
  • women during pregnancy and lactation
  • Children and adolescents in the growth phase
  • Athlete (7)

In these people, the daily need for iron is increased, since the oxygen and energy turnover is increased and thus more hemoglobin is formed. However, this can only happen if the body has enough iron available to produce the red blood pigment.

disturbance of iron absorption

Another reason for iron deficiency anemia can be an inhibition of the absorption of iron in the body. This is considered a rather rare cause, but we would like to explain here what exactly is meant by the inhibited absorption by the body.

Normally, the element iron, which we ingest through food, is processed by the body. In some cases, however, our body cannot absorb the iron sufficiently. Reasons for this can be, for example, inflammatory bowel diseases or stomach reductions. There is also a risk of impaired iron absorption when taking certain medications such as antacids or when consuming large amounts of coffee, black tea or rhubarb (2).

What are the differences between iron deficiency and iron deficiency anemia?

You are probably wondering what exactly is the difference between iron deficiency and iron deficiency anemia. We want to explain this to you in the following section.

Iron deficiency can lead to iron deficiency anemia.

A low intake of iron can lead to a deficiency in it. This condition defines iron deficiency, which clinically can lead to iron deficiency anemia (10). Anemia is present when the concentration of hemoglobin falls below the normal value.

Such standard values ​​are defined according to gender and age-specific criteria. Accordingly, an iron deficiency is the prerequisite for the development of iron deficiency anemia, because this results from the lack of the element.

In both stages, a blood test must be performed for diagnosis. Specialists can then use the laboratory values ​​to determine whether there is a reduced iron concentration in the patient's blood (11).

When is an iron deficiency or iron deficiency anemia present?

An iron deficiency is diagnosed based on the symptoms and a blood test, when there is an iron deficiency, a reduced number of red blood cells can be seen. A depletion of the iron store ferritin would also be recorded (13).

The normal amount of iron in transferrin is about 6.3 to 30.1 micromoles per liter in men and about 4.1 to 29.5 micromoles per liter of blood in women. Transferrin is the iron transport protein in the blood. If the value falls below 10 percent and the ferritin value is also low, then there is usually an iron deficiency (11).

Blood is measured for iron concentrate

Iron deficiency and iron deficiency anemia are diagnosed by examining the blood. Above all, the iron concentration is measured and the hemoglobin value is checked. (Image source: / Unsplash)

If there is iron deficiency anemia, the specialist usually recognizes red blood cells with a comparatively small size of less than 76 fl. Fl stands for femtoliter and is a unit of volume in medicine to indicate laboratory values. Furthermore, in such a case there would be a reduced hemoglobin content (11).

What are the stages of iron deficiency anemia?

There are three stages of iron deficiency, each with slightly different symptoms. The three stages are as follows:

  1. depletion of iron stores
  2. Iron-poor erythropoiesis
  3. Iron Deficiency Anemia (12)

The depletion of iron stores and low-iron erythropoiesis are the precursors to iron-deficiency anemia. This is the most pronounced form of iron deficiency. In the list below, we explain the various stages in more detail.

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No problem!

With our Sundt iron capsules + vitamin C you can:

  • keep your energy levels high on the most stressful days🏃
  • be sure you are getting enough iron🌿

Our vegan iron capsules are now available with a 21% discount *

Sunt Icon

*The discount is automatically applied to the product

  • Depletion of iron stores: In the first stage, the body lacks a supply of iron. In order to continue to ensure a supply of the mineral, the body falls back on the stored iron in this case, which means that the iron stores are slowly used up. The result is a shortage of supply, which leads to a reduction in the level of ferritin in the blood. In this first stage there is no anemia, i.e. it is not yet anemia (14).
  • Low-iron erythropoiesis: In the second stage, the formation of red blood cells is disrupted because the bone marrow produces fewer and fewer erythrocytes. As a result, the iron reserves are again massively reduced. As a result, the cells are undersupplied with iron, since the body only has very small amounts of the element. The hemoglobin value is usually still just within the normal range (14).
  • Iron deficiency anemia: Iron deficiency anemia describes the third stage of iron deficiency. At this point, there is already a severe iron deficiency. The hemoglobin value usually falls below the normal value and there is an insufficient supply of oxygen to the body cells. This stage should be examined and treated by a doctor as soon as possible (14).

These three stages are traditionally distinguished in the case of iron deficiency. Irrespective of whether someone is in the first, second or even third stage, a medical examination and then, if necessary, treatment should be sought urgently.

Symptoms of iron deficiency stages

The symptoms of iron deficiency or anemia, which we have already explained to you earlier in this article, can also vary depending on the stage at hand. In the case of iron deficiency in the first and second stages, the following symptoms (6,14) can occur, for example:

  • Pale skin, hair loss and brittle nails
  • Severe tiredness, weakness, loss of performance and problems concentrating
  • Forgetfulness, nervousness and inner restlessness
  • Poor appetite, gastrointestinal problems and difficulty swallowing
  • Dizziness, palpitations and breathing problems
  • Increased susceptibility to infections

In the context of the second and especially the third stage, the following characteristics (14) can also be recorded in the affected patients in addition to the symptoms just mentioned:

  • Dark circles and blurred vision
  • Headache and sounds in the ear
  • Dry skin and cracked corners of the mouth
  • Mucosal changes and muscle cramps
  • Severe cold and absence of menstruation in women

In the case of particularly severe iron deficiency anemia, the following symptoms (14) appear as warning signals from the body:

  • Intense feeling of drowsiness and absence
  • Rapid heartbeat and shortness of breath

An iron deficiency (anemia) therefore has varying symptoms depending on the stage at hand, some of which can be severe and affect the affected person's life. That is why it is important that a deficiency of the element is treated.

When can iron deficiency anemia become dangerous?

An iron deficiency should initially be classified as not life-threatening, but the stage plays a decisive role in the risk of the deficiency symptoms. A severe deficiency in stages two to three can be dangerous if the iron deficiency anemia remains undetected and untreated for a long time.

In this case, the body cells cannot be supplied with enough oxygen due to the prevailing anemia (14). This can damage the body over time. Because of this, if you suspect iron deficiency, you should act quickly and consult your doctor so that the deficiency cannot progress to a higher, risky stage.

Why do women experience iron deficiency anemia more often than men?

Women are among the first risk group for iron deficiency and iron deficiency anemia. According to studies, more than 30 percent of women of childbearing age experience an undersupply of iron, which is considered the most common micronutrient deficiency worldwide (15).

The reason for this is often the monthly menstrual period. Here, women lose blood almost every month, which in turn leads to iron loss. If the depleted stores are not then adequately replenished, a deficiency can occur, which can develop into iron deficiency anemia.

Woman lying on her stomach

Women of childbearing age lose blood monthly through their periods. In addition, the iron requirement is increased during pregnancy and breastfeeding, which means that women are at high risk of suffering from iron deficiency anemia. (Image source: Vladislav Muslakov / Unsplash)

In addition, a woman's iron requirement increases significantly during pregnancy and breastfeeding. Therefore, even in these phases of life, a woman may be at increased risk of iron deficiency (7). Here, too, countermeasures should be taken with the right dosage in order to avoid iron deficiency anemia.

Which doctor is responsible for iron deficiency anemia?

If you suspect iron deficiency, you should either see your family doctor or make an appointment with a specialist in hematology, who is an expert in blood diseases.

In both cases, a blood test should be carried out by a doctor for diagnosis. The experts can then use the laboratory values ​​to determine whether there is a reduced iron concentration in the blood (11).

Iron deficiency is primarily diagnosed by blood counts.

When making a diagnosis, however, a distinction must also be made based on the causes of the iron deficiency. For example, in the case of iron deficiency anemia due to chronic inflammatory diseases, it is necessary to consider possible increased limit values ​​for serum ferritin. In such a case, transferrin saturation must also be assessed (16).

The diagnosis of iron deficiency anemia is usually uncomplicated. Only when the deficiency of the element occurs in connection with inflammatory diseases, as mentioned above, is the diagnosis somewhat more difficult to make and the course of treatment correspondingly more complex (17). Iron deficiency anemia can be diagnosed by measuring serum ferritin and hemoglobin levels.

Treating Iron Deficiency Anemia: The best advice and information for treating Iron Deficiency Anemia

In the following section we offer you a helpful overview with the best advice and information for treating iron deficiency anemia.

If you suspect that you might be suffering from an iron deficiency, you should urgently consult a specialist in addition to the tips below. He will be able to give you a clear diagnosis and then treat you professionally.

Treatment options for iron deficiency anemia

There are different treatment strategies for iron deficiency anemia. We have created a list for you here in which you will find some of the most common causes with the typical treatment options.

  1. Blood loss Menstrual period: This affects the women of childbearing age. In this case, doctors would often recommend taking iron supplements to compensate.
  2. Blood loss chronic bleeding: In the case of blood loss due to inflammatory diseases, surgical therapy is usually scheduled after consultation with a doctor.
  3. Inadequate dietary iron intake: Here, supplementation and an iron-focused diet plan are used with the aim of preventing future iron deficiency (1).
  4. Increased iron requirement: Groups of people who have an increased requirement for the element should take supplements to prevent iron deficiency anemia.
  5. Impaired iron absorption: In such a case, after unsuccessful administration of oral iron supplements, your doctor may switch to administration of intravenous iron.

The decision as to which treatment method to use is made by the physician primarily on the basis of individual disease-related and person-related criteria (16). The treatment method therefore depends on the severity of the iron deficiency on the one hand and the underlying cause on the other.

In any case, a doctor should be consulted to determine the appropriate treatment method and also the dosage of iron.

taking iron supplements

In the case of iron deficiency anemia, doctors often recommend taking oral preparations. Such preparations often have side effects that impair the effectiveness of the drug. For this reason, intravenous iron is increasingly used in order to achieve a particularly rapid normalization of the iron value (17).

There is oral and intravenous iron administration.

In patients where oral intake of the preparations is less effective, intravenous administration can be used (5). These preparations are becoming increasingly popular because they compensate for functional iron deficiency just as quickly as a deficiency in the context of inflammatory diseases (17).

Many people are of the opinion that intravenous iron preparations are extremely effective and, above all, safe. However, it should be noted that the question of long-term tolerability and safety of high-dose iron intake in particular requires further research and that the long-term side effects of intravenous iron still have to be evaluated (17).

dosage of iron

The German Society for Nutrition (DGE) recommends certain amounts for daily iron intake, which vary depending on age group and gender. In the following two tables (18) we have listed the guide values ​​of the DGE for you as an overview. The first table (18) shows the recommended daily iron intake for men.

age of men Recommended iron intake in mg per day
0 to 12 months 0.5 to 8
1 to 10 years 8 to 10
10 to 15 years 12
15 to 19 years 12
19 to 65 years and older 10

The second table (18) lists the reference values ​​for the female gender, with the values ​​for pregnant and breastfeeding women being listed separately at the end.

age of women Recommended iron intake in mg per day
0 to 12 months 0.5 to 8
1 to 10 years 8 to 10
10 to 15 years 15
15 to 51 years 15
51 to 65 years and older 10
pregnant women 30
breastfeeding 20

It should be noted that athletes also have an increased need for iron and are at increased risk of suffering from iron deficiency anemia. In this group of people, the need is increased because the oxygen and energy turnover is greater.

Children, women and athletes have high iron requirements.

Athletes have an iron requirement that is almost twice as high as that of non-athletes. This is e.g. Partly due to perspiration, since the body loses iron when sweating. The high oxygen and energy turnover also plays a role because a larger amount of hemoglobin and blood is formed in this way (7).

For the correct absorption of iron, the dosage should therefore depend primarily on age, gender and physical activity. This applies equally to the intake of the element through food and through supplementation with preparations.

Treat iron deficiency anemia with proper nutrition

Since iron deficiency anemia already describes the advanced, severe stage of iron deficiency, in such cases it is usually not recommended to treat the deficiency with an iron-rich diet. High-dose preparations are then often necessary in order to be able to restore a stable iron level in the body.

As a result, as well as in the case of a slight iron deficiency, a targeted diet can be used to cover the daily iron requirement. In the following table (19,20) you can see foods that are particularly rich in iron.

Groceries Iron in mg per 100 g
blood sausage 17
soybean flour 15
wheat bran 15
cocoa 12.5
pumpkin seeds 12.5
sesame seeds 10
liver (beef) 9.5
pine nuts 9.2
lenses 8th
shellfish 7.2
egg 7.2
kidney beans 6.4

A diet rich in iron promotes the absorption of iron in the body (21). It is often thought that vegetarians and vegans are at risk of iron deficiency anemia because they do not consume animal sources of iron and the element is more difficult for the body to absorb from plant sources .

However, vegetarians and vegans can counteract this by getting plenty of vitamin C and organic acids from the diet. This is said to promote the absorption of iron from plant sources in the body.

A vegetarian or vegan diet can lead to a high iron intake if you consciously choose iron-rich foods . According to the current state of knowledge, people who are e.g. In fact, those who eat a T. or exclusively plant-based diet are no more likely to suffer from iron deficiency or iron-deficiency anemia than the general population (9).

Length of treatment and sick leave for iron deficiency anemia

How long should iron deficiency anemia be treated and do you actually get sick leave with such a diagnosis? In order to answer these questions, it is important to show that in the case of severe iron deficiency anemia it usually takes a long time before the completely empty iron stores are refilled.

That is why we recommend a therapy length of around three to six months. However, after up to ten days, an improvement in the blood count should be evident based on the formation of new blood cells and an increase in the hemoglobin value (22).

If you suspect iron deficiency anemia, you should consult your doctor. In many cases, GPs or specialists can issue a sick leave so that the patient receives sick pay and is released from his work obligation for a certain period of time. Your doctor will decide how long such sick leave is for iron deficiency anemia, depending on the severity of the undersupply and the cause and further action.


In this article you have learned that iron deficiency is the most common of the micronutrient deficiencies worldwide and that certain groups of people, such as children and adolescents, women of childbearing age and pregnant women, breastfeeding women and athletes are particularly at risk.

Iron deficiency often goes undetected for a long time and can therefore develop into iron deficiency anemia without the appropriate treatment. If, based on the symptoms presented above, you suspect that you are suffering from an iron deficiency, we definitely recommend that you speak to a specialist about it. In addition, our advice and information can be used to support your doctor's treatment method.


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