Iron

Iron is an essential trace element needed for numerous vital processes in the body. About 70% of the body’s iron is found in the hemoglobin of red blood cells and in the myoglobin of muscle cells. These proteins are crucial for binding and transporting oxygen in the blood as well as supplying oxygen to the muscles. The remaining iron is bound in various enzymes and stored in body cells, where it is needed for metabolic processes and immune defense. Since the body cannot produce iron itself, it must be absorbed through food. After absorption in the small intestine, iron is bound to the transport protein transferrin and transported to the respective organs and to the bone marrow, where it is needed for the formation of new blood cells. Excess iron is stored in ferritin, which is primarily found in the liver, spleen, and bone marrow. A well-filled iron store is very important to ensure a continuous supply to the body, as a deficiency can lead to blood disorders, also known as anemia, and various health complaints.

To determine the iron status in the body more precisely, a blood test is conducted where multiple parameters are analyzed and contextualized. The most important values for assessing iron metabolism are ferritin, transferrin saturation (TSAT), hemoglobin, and serum iron:

Therefore, a holistic consideration of these values is crucial, as individual values viewed in isolation cannot provide a complete picture of the body’s iron supply.

An excess of iron in the body can bring serious health consequences and should definitely be addressed. The most common symptoms of iron excess include fatigue, joint pain, and organ damage, particularly to the liver and heart. Long-term, a high iron concentration over an extended period can lead to organ damage, as excess iron causes oxidative stress in cells, resulting in damage.

Possible causes of iron excess include genetic disorders such as hemochromatosis, where the body absorbs too much iron and does not adequately excrete it. Iron infusions or excessive iron intake through dietary supplements can also lead to an excess. Inflammation in the body, which can occur with chronic diseases, can also negatively affect iron metabolism and lead to elevated iron levels.

Blood values indicating an iron excess are a transferrin saturation of over 45% and a ferritin value of more than 1,000 ng/ml. In such cases, it is extremely important to clarify the exact cause and initiate appropriate treatment to avoid long-term organ damage.

Existing iron deficiency can cause a variety of health problems in the long term, as iron is essential for the body’s oxygen supply and energy production. The most common symptoms of iron deficiency include fatigue, dizziness, weakness, and an unusual feeling of coldness. Additionally, typical cracking of the lip corners and paleness may occur. Since iron is responsible for the formation of hemoglobin in the blood, low iron levels often lead to anemia, which can severely impair overall well-being.

The causes of iron deficiency are often very diverse. Frequent blood loss, such as can occur with very heavy menstrual bleeding or internal bleeding, is one of the main causes. A one-sided diet that includes few iron-rich foods such as meat, legumes, or green vegetables can also lead to a deficiency. Furthermore, conditions such as celiac disease or chronic intestinal diseases, like Crohn’s disease or ulcerative colitis, can impair iron absorption in the intestine and thus contribute to the development of a deficiency.

Iron is found in many foods, however, the type of iron differs depending on the source. There is heme iron, which is primarily found in animal products, and non-heme iron, which comes from certain plant sources. Heme iron from animal products is generally better absorbed by the body and is therefore one of the preferred iron sources. In contrast, iron from plant sources is often less bioavailable, meaning it is not absorbed as effectively. This is because non-heme iron in plant foods is often bound to certain plant compounds such as phytates, which can inhibit absorption in the intestine. To improve the absorption of non-heme iron, it is recommended to combine these foods with vitamin C-rich foods such as citrus fruits or bell peppers, as vitamin C promotes iron absorption and overcomes the inhibitors in plant iron.

Food Iron Content (per 100g)

Food Iron Content (per 100g)

A balanced diet with a variety of iron-rich foods from both animal and plant sources initially helps to meet iron requirements, especially for people suffering from iron deficiency. It is therefore particularly advisable to combine plant iron sources with vitamin C-rich foods to improve iron absorption.

In addition to a balanced diet that includes sufficient iron sources, iron supplements can also be a helpful additional support in certain cases. When iron requirements cannot be met through diet due to illnesses, unbalanced nutrition, or increased demands, such as during pregnancy, iron supplements can be used effectively. These supplements help the body replenish iron stores and alleviate symptoms of iron deficiency. Generally, the first approach should be to meet iron requirements through the consumption of iron-rich foods. However, if this is insufficient or the requirement is particularly high, as in the case of existing iron deficiency anemia, taking iron supplements may be necessary. It is important that iron-containing supplements are only taken after consultation with a doctor to determine the correct dosage and form of the supplement. This way, the supplements can be tailored to individual needs to optimally support the body.

Iron tablets are a commonly used form of oral iron supplements. They are specifically used to treat iron deficiency and iron deficiency anemia. Iron tablets typically contain iron compounds such as iron(II) sulfate or iron(III) polysaccharide complexes, which help the body meet its iron requirements and replenish the body’s iron reserves. The intake of iron tablets is adjusted according to the severity of the iron deficiency. The tablets should generally be taken with water, preferably on an empty stomach, to optimize iron absorption. In some cases, it may be helpful to combine the intake with vitamin C, as vitamin C supports iron absorption. Despite their effectiveness, iron tablets can sometimes cause side effects. The most common include nausea, constipation, and stomach discomfort. These symptoms often occur when the tablets are taken in very high doses or when they are not properly combined with meals. Overall, iron tablets are an effective way to meet iron requirements in deficiency states. However, they should always be taken under medical supervision to ensure the correct dosage and form of the preparation and to minimize possible side effects.

Lactoferrin is an iron transport protein that naturally occurs in milk and other bodily fluids. It plays an important role in binding and transporting iron, which can improve absorption in the intestines. A particular advantage of lactoferrin is that it not only supports iron absorption but also possesses antimicrobial properties that can inhibit bacterial growth in the intestines. It is frequently used in iron supplements to increase iron bioavailability while simultaneously reducing side effects such as stomach discomfort or constipation.

Liposomal iron is another specialized form of iron supplement, where iron is encapsulated in small liposomes. These liposomes improve iron absorption by protecting it from stomach and intestinal damage, making it more stable. A major advantage of liposomal iron is that it causes fewer gastrointestinal discomforts, and its tolerability is often significantly better compared to conventional iron supplements. It is preferred for particularly sensitive individuals, as it is absorbed directly into the bloodstream without heavily burdening the digestive tract.

Iron bisglycinate is a chelated compound where iron is bound to an amino acid called glycine. This form of iron has very high bioavailability and is exceptionally well absorbed by the body without causing the usual gastrointestinal discomfort. The advantage of iron bisglycinate lies in its optimized iron absorption while simultaneously reducing the risk of side effects such as nausea and constipation. It is one of the preferred forms in iron supplements because it not only rarely causes side effects but can also be very well absorbed by the body.

Iron pyrophosphate is an iron compound that exhibits high stability. This form of iron has extremely low toxic effects on the body and can be efficiently absorbed, making it particularly well-tolerated. Iron pyrophosphate is frequently used in iron supplements designed for long-term use. A significant advantage of this form is its suitability for the long-term treatment of iron deficiency, as it gently builds up iron reserves in the body.

Ferrous sulfate is one of the most commonly used forms of iron in supplements. It contains iron in its divalent form, which enables good bioavailability. However, this form of iron is often associated with gastrointestinal discomfort such as nausea, constipation, or abdominal pain, especially when taken on an empty stomach. To minimize side effects with this preparation, ferrous sulfate should ideally be taken with some food.

Ferrous gluconate is another form of iron that is well-absorbed by the body and often causes fewer stomach problems than ferrous sulfate. It is frequently used in iron supplements that offer high bioavailability while also being well-tolerated. Ferrous gluconate is suitable for individuals who are sensitive to other iron preparations. This form of iron has the ability to efficiently supply the body with iron while reducing the risk of side effects.

Ferrous fumarate is an iron compound that is also particularly well-absorbed by the body. It is commonly used in iron supplements intended for the treatment of iron deficiency and anemia. Ferrous fumarate has very high bioavailability and is also well-tolerated compared to other iron preparations. It can help efficiently regulate iron levels while alleviating symptoms of iron deficiency. Like other forms of iron, it may still cause stomach discomfort in some individuals, which is why taking it with food is recommended.

Iron citrate is another highly bioavailable form of iron that exhibits greater solubility compared to other iron preparations. This form of iron is well absorbed by the body and typically causes fewer side effects. Iron citrate is often used in liquid iron supplements and is therefore well-suited for individuals who have difficulty swallowing tablets.

Iron carbonate is a form of iron that is absorbed relatively slowly by the body. It is often used in iron supplements designed for long-term iron supplementation. This form of iron has moderate bioavailability and can be beneficial for people who have previously reacted sensitively to other iron forms. Due to its slow release, iron carbonate is well-suited for people who need a constant, lower iron intake.

Heme iron is a form of iron derived from animal sources and is found in hemoglobin and myoglobin. It has the advantage of very high bioavailability and can be efficiently absorbed by the body. Heme iron is particularly well utilized by the body without causing the typical gastrointestinal discomfort that can occur with other iron supplements. Due to its better absorption, heme iron is a preferred choice for treating iron deficiency, especially in people who have difficulty absorbing non-heme iron.

Iron(III) hydroxide polymaltose complex is a well-tolerated form of iron that is already used in many modern iron supplements. This compound consists of iron bound to polymaltose, a sugar complex. This allows it to be gently released in the body and cause fewer stomach issues than other forms of iron. It has high bioavailability and is frequently used in preparations intended for long-term iron supplementation.

Iron sucrose is an iron compound primarily found in liquid iron preparations. It has high solubility and is well absorbed by the body. Iron sucrose is often used in intravenous iron preparations, such as in cases where oral preparations are insufficient. This is particularly advantageous for patients who have difficulty absorbing iron in other ways. This form of iron is highly effective and provides a rapid way to regulate iron levels in the body.

We particularly recommend lactoferrin and liposomal iron, as these forms of iron offer especially high bioavailability, meaning they can be absorbed and utilized more efficiently by the body. Lactoferrin is a naturally occurring protein that binds and transports iron, thereby improving iron absorption in the intestine while also possessing anti-inflammatory properties. These characteristics make lactoferrin particularly beneficial for people who have difficulties with conventional iron supplements or suffer from inflammatory bowel diseases. Iron bisglycinate and iron pyrophosphate are also excellent options for iron supplementation, as they generally come with very high tolerability.

Iron bisglycinate is another recommended iron compound for dietary supplements. Due to its binding to an amino acid, it is better absorbed in the body and can thus reduce the risk of gastrointestinal complaints such as nausea or constipation. It is particularly gentle on the digestive tract and is excellently suited for individuals who are sensitive to conventional iron preparations.

Iron pyrophosphate is another form that causes fewer side effects compared to other types of iron. This form has a relatively low toxicity and enables long-effective iron supply without unnecessarily burdening the body. It is well-suited for long-term use to optimize iron levels slowly but steadily.

Together, these iron supplements offer a gentle and effective way to improve iron balance, especially for individuals who tend to have sensitive stomach reactions or experience side effects from conventional iron preparations such as iron(II) sulfate. They help to remedy iron deficiency in a gentle manner without putting additional strain on the body.

Iron infusions are typically used when a severe iron deficiency is present that no longer responds to treatment with oral iron preparations, or in patients who require rapid and effective replenishment of iron reserves. This form of treatment enables iron to be introduced directly into the bloodstream, resulting in a rapid improvement in iron balance. Especially for patients who have difficulty absorbing iron orally due to gastrointestinal disorders or other health problems, iron infusions represent an important therapeutic option. The administration of an iron infusion typically takes place in a doctor’s office or a clinic. The patient receives the infusion intravenously, with the iron being administered in a special solution. This allows for quick absorption of the iron and is particularly helpful when treatment cannot be provided through tablets or when the deficiency is very severe. Commonly used preparations include Ferrlecit and Venofer, both of which contain a form of iron(III) hydroxide polymaltose complex and are very well tolerated. Iron infusions offer an efficient way to replenish iron levels without burdening the digestive tract.

Iron carboxymaltose is a form of iron infusion used to rapidly replenish iron stores in the body, particularly in patients affected by severe iron deficiency. A well-known preparation containing iron carboxymaltose is Ferinjec. This infusion is typically administered intravenously and offers a quick way to stabilize iron levels without burdening the digestive tract. The effect of iron carboxymaltose is particularly advantageous as it has high bioavailability, allowing the body to absorb the iron directly. In just a few sessions, iron reserves can be quickly replenished, which is particularly important for patients with acute iron deficiency or those who do not respond to oral iron preparations. Administration is performed under medical supervision, as the infusion can, in rare cases, cause side effects such as allergic reactions or mild circulatory problems.

Iron sucrose, an iron preparation contained in products such as Venofer. It is commonly used to treat patients with severe iron deficiency who cannot tolerate oral iron preparations or who require faster and more effective replenishment of iron stores. This form of iron infusion is particularly suitable for patients with chronic conditions that lead to poor iron absorption, such as renal insufficiency or gastrointestinal problems, where oral preparations cannot be optimally absorbed. The effect of iron sucrose is also rapid and effective, as the iron enters directly into the bloodstream. This infusion helps to quickly replenish iron stores in the body, leading to an improvement in hemoglobin levels and associated symptoms such as fatigue, weakness, and shortness of breath.

Iron isomaltoside, an iron preparation contained in Monofer. It represents an excellent alternative for patients suffering from chronic diseases. Chronic conditions can often impair iron absorption. This form of iron is particularly beneficial for patients with renal insufficiency, inflammatory bowel diseases such as Crohn’s disease or ulcerative colitis, or other health problems. The effect of iron isomaltoside is as effective as other iron infusions. The iron enters directly into the bloodstream and can be quickly incorporated into iron stores, significantly improving the symptoms of iron deficiency. This infusion enables rapid normalization of hemoglobin levels without burdening the digestive tract or causing side effects such as nausea or constipation, which are common with oral preparations. Iron isomaltoside is characterized by very good tolerability and is a suitable option for patients who cannot use other iron preparations due to intolerances.

Iron gluconate, contained in products such as Ferrlecit, is a very commonly used form of iron infusion for treating iron deficiency. This form of iron offers a rapid and effective way to replenish iron stores in the body, especially in patients who do not respond to or cannot tolerate oral iron preparations. The effect of iron gluconate is based on the direct entry of iron into the bloodstream, where it is quickly incorporated into hemoglobin levels, leading to rapid improvement of iron deficiency symptoms. This infusion enables stabilization of iron status and promotes normal blood formation. Iron gluconate has very good bioavailability, meaning that the iron is efficiently and quickly absorbed by the body. Administration typically occurs under medical supervision, as the infusion can sometimes cause mild side effects such as headaches, nausea, or circulatory problems. However, iron gluconate is generally considered well-tolerated and represents an effective option for treating iron deficiency.

Iron absorption in the body is a complex process, with only about 20% of oral iron from food actually being absorbed. This low absorption rate is one reason why many people may suffer from iron deficiency despite consuming an iron-rich diet. However, the body has various mechanisms to regulate and improve iron absorption. It is particularly important to increase the bioavailability of iron to ensure that the body can absorb the required amount.

A crucial factor in promoting iron absorption is the intake of vitamin C. Vitamin C plays a significant role by converting non-heme iron into a more absorbable form. This conversion makes it easier for the body to absorb and utilize iron from plant foods such as spinach, lentils, or oats. Sufficient intake of vitamin C from foods like citrus fruits, bell peppers, or broccoli can therefore significantly increase iron absorption.

On the other hand, there are also inhibiting substances that can impair iron absorption. Substances such as phytates, found in whole grain products, legumes, and seeds, can reduce iron absorption by binding to iron and blocking its absorption in the intestine. Tannins, contained in tea and coffee, have a similar effect. They can also make iron absorption more difficult by binding with iron and inhibiting absorption in the small intestine.

To optimize iron absorption, it is recommended to consume plant-based iron sources in combination with vitamin C-rich foods. Reducing the consumption of tea or coffee during meals, as well as moderating the intake of whole grain products or legumes, can be helpful approaches to increase iron absorption.

Iron combination supplements are special nutritional supplements that consist of iron combined with other nutrients that support iron absorption or enhance the effect of iron in the body. These preparations are particularly useful for people suffering from iron deficiency who simultaneously want to benefit from the synergistic effects of other vitamins or minerals to efficiently replenish their iron reserves and improve health. The combination of iron with vitamin C is a common example, as vitamin C significantly improves the absorption of iron from plant sources. Additionally, many preparations also include folic acid, vitamin B12, or copper. These vitamins and minerals not only promote iron absorption but also contribute to the formation of hemoglobin and support blood production. The advantage of such combination supplements lies in their comprehensive support of the entire iron metabolism and their ability to improve the treatment of iron deficiency on multiple levels.

The combination of iron and vitamin C plays an essential role in optimizing iron absorption in the body, especially for non-heme iron. Non-heme iron is a form of iron found in plant foods. Vitamin C promotes the absorption of iron by converting it into a more readily absorbable form. Non-heme iron is fundamentally more difficult for the body to absorb than heme iron, which is contained in animal products. Through the additional intake of vitamin C, the bioavailability of non-heme iron is significantly increased, allowing the body to absorb more of the nutrient. The effect of vitamin C on iron absorption is primarily explained by its ability to convert iron from plant sources into a more soluble form that can be more easily absorbed through the intestinal mucosa. A practical approach to improving iron absorption is to combine iron-rich foods with vitamin C-rich foods. These combinations not only promote iron absorption but also provide additional benefits for a healthy and balanced diet. This simple adjustment to meals optimizes iron absorption, which is particularly important for people with higher iron requirements or iron deficiency.

Folic acid, also known as vitamin B9, plays a crucial role in blood formation, particularly in the production of red blood cells. Together with iron, folic acid is an essential nutrient for the body’s blood health. Iron is needed for hemoglobin synthesis, the protein that transports oxygen in red blood cells, while folic acid is responsible for the multiplication and maturation of red blood cells. These two nutrients work hand in hand to support the formation of healthy red blood cells and ensure a well-functioning blood circulation. Therefore, a deficiency in iron and folic acid can lead to various forms of anemia. With iron deficiency, the body cannot produce enough hemoglobin, which leads to inadequate oxygen supply to organs, and symptoms such as fatigue, weakness, and pallor can characteristically occur. Folic acid deficiency also impairs blood formation and can thus lead to a special form of anemia known as megaloblastic anemia. In this anemia, red blood cells are larger than normal and therefore less functional, which impairs the blood’s ability to transport oxygen. Both nutrients are therefore crucial not only for blood health but also for general well-being. Adequate intake of iron and folic acid from food or through supplements ensures that the body produces sufficient red blood cells that can efficiently transport oxygen. Especially during pregnancy, or in people with chronic diseases, the combination of these two nutrients is particularly important to promote healthy blood formation.

Vitamin B12, also known as cobalamin, plays another essential role in blood formation and maintaining a healthy nervous system. Working in conjunction with iron, vitamin B12 is therefore a crucial factor for the production of red blood cells in the bone marrow. Both nutrients contribute to the formation and maturation of red blood cells. Iron is needed for the formation of hemoglobin, the iron-containing protein in red blood cells, while vitamin B12 is essential for cell division and cell maturation. A deficiency in vitamin B12 can lead to an anemic condition known as megaloblastic anemia. In this disorder, red blood cells are unusually large and still immature, which impairs their ability to transport oxygen efficiently. Such a deficiency can therefore cause symptoms similar to those of iron deficiency.

The relationship between iron and vitamin B12 is particularly noteworthy because both nutrients are required for energy production in the body. Vitamin B12 supports energy metabolism by participating in DNA synthesis and enabling the production of red blood cells, which leads to increased energy. In combination with iron, vitamin B12 helps optimize blood formation and iron metabolism, allowing the body to deliver the necessary amount of oxygen to its tissues and organs.

Proper intake of both iron and vitamin B12 is therefore crucial for blood health, energy production, and the nervous system. A deficiency in vitamin B12 or iron can consequently lead to impairment of these functions and negatively affect overall health. Therefore, it is important to ensure a balanced diet in which both nutrients can be adequately supplied to the body.

Zinc is an essential mineral that fulfills a variety of important functions in the body. It primarily supports the immune system, plays a key role in wound healing, promotes cell growth, and contributes to protein synthesis and gene expression. Zinc is also important for hormone production and acts as an antioxidant that prevents cell damage from free radicals. Since the body cannot store zinc, it must be regularly consumed through the diet. While zinc has many positive health effects, an excessive zinc level in the body can impair iron absorption. By competing with iron for the transporter during intestinal absorption, zinc can reduce the bioavailability of iron. This means that high amounts of zinc can decrease the efficiency of iron absorption from food or supplements, which can lead to iron deficiency with long-term zinc excess. Therefore, it is important that the ratio of iron and zinc in the body remains balanced. In practice, this means that patients who take both iron and zinc through supplements should ensure that they choose dosages that do not create an excess of either mineral.

Iron requirements vary throughout life as different life phases place different demands on the body. During certain phases, such as pregnancy, growth, or advanced age, iron requirements change. This is due to varying needs for oxygen supply, cell growth, and blood functions. Therefore, it is important to ensure adequate iron supply during these phases to avoid deficiency states and associated health problems such as anemia.

During pregnancy, iron requirements are significantly increased as the body needs more iron to support placental circulation and promote fetal growth. Iron plays a central role in the formation of hemoglobin, which transports oxygen from the mother to the fetus. As the mother’s blood volume increases during pregnancy, the amount of hemoglobin must also increase to meet the rising oxygen demand. During this time, an inadequate iron status can lead to iron deficiency, which in turn increases the risk of anemia. Iron deficiency anemia in pregnancy can not only affect the mother’s health but also negatively impact the growth and development of the fetus, potentially leading to premature birth or low birth weight. To prevent the development of iron deficiency during pregnancy, taking iron supplements is often recommended, especially when dietary intake alone cannot meet iron requirements. Iron tablets or iron solutions can help replenish iron reserves and prevent the development of anemia.

Iron requirements are particularly high during childhood, as iron is crucial for growth, development, and cognitive performance. Iron is a central component of hemoglobin, responsible for oxygen transport in the blood, and therefore plays an important role in brain development and blood formation. Iron deficiency in childhood can often lead to developmental disorders, concentration problems, and delayed motor development. Especially in infants and young children, who are still in a rapid growth phase, inadequate iron status can have negative effects on mental and physical development. Iron deficiency in children often manifests through symptoms such as paleness, fatigue, irritability, and loss of appetite. It is generally recommended to promote iron supply through an iron-rich diet including meat, legumes, whole grain products, and leafy green vegetables. In some cases, it may also be necessary to use iron preparations or supplements to meet requirements, especially when intake through diet alone is insufficient or iron requirements are particularly high due to growth spurts.

In the following, we want to answer your questions about the trace element iron in more detail, to give you an even better understanding of supplementation, improving bioavailability, and iron deficiencies.

The information listed contains relevant topics and serves to improve understanding.