What is iron? The biological basis of an essential trace element
Iron is a trace element that must be present in the diet for proper growth and function of the organism. . Although the body only needs very small amounts – ranging from micrograms to milligrams – it is an essential part of various enzymes and proteins . One of the best-known functions of iron is its role in the production of red blood cells .
In the body, iron serves as a crucial component of hemoglobin, the protein in red blood cells responsible for transporting oxygen from the lungs to the tissues . In addition, it plays a role in releasing energy in the cells and supports the normal functioning of the immune system. .
The two forms of iron: Heme iron versus non-heme iron
Iron in our diet comes in two different chemical forms, each of which has a different impact on how efficiently the body can absorb the nutrient .
- Heme iron: This form is found exclusively in animal products . Heme iron is generally better and more efficiently absorbed by the body .
- Non-heme iron: This type of iron is mainly found in plant foods . Non-heme iron absorption is more variable and strongly influenced by other dietary factors .
For a balanced household it is important to understand how these forms work together and how absorption can be optimized.
The influence of vitamin C on iron absorption
The absorption of non-heme iron from plant sources can be significantly enhanced by the simultaneous consumption of vitamin C . Vitamin C helps keep the iron in a form that can be more easily absorbed through the intestinal wall .
In practice this means that drinking a glass of orange juice or eating vegetables rich in vitamin C during an iron-rich meal contributes to better utilisation of the nutrients present. . Conversely, certain substances, such as calcium in dairy products, can actually influence iron absorption because they play a role in the complex iron metabolism in the intestine .
Iron Metabolism and Storage: How the Body Regulates Iron
The human body has no active way to excrete excess iron . Therefore, the regulation of absorption in the small intestine is extremely strict . Once absorbed, iron is transported through the bloodstream by the protein transferrin to where it is needed, such as the bone marrow for the production of blood cells .
When there is more iron available than is immediately needed, it is stored in the form of ferritin in the liver and other tissues . A healthy balance in this supply is essential; a deficiency can lead to reduced oxygen delivery in the body, which often manifests as fatigue or pale skin. .
Special situations: Iron overload (Hemochromatosis)
In some individuals, the natural regulation of iron absorption is disturbed. In primary hemochromatosis, a hereditary condition, the body structurally absorbs too much iron from food . This excess iron builds up over time in organs such as the liver and heart, which can lead to complications without proper guidance. This condition underlines how precise the iron balance in the human body is.
Summary
Iron plays a fundamental role in oxygen transport and energy supply in our body . By consciously choosing a combination of heme iron and non-heme iron, and supporting this with vitamin C-rich food, absorption can be effectively supported . A well-regulated iron balance directly contributes to maintaining vitality and proper functioning of biological processes .
FAQ: Frequently asked questions about iron
Which foods contain the most iron? Heme iron is found in animal products such as meat and fish . Non-heme iron is found in plant sources such as whole grains, legumes and green leafy vegetables .
When is the best time to take iron? Iron is generally best absorbed on an empty stomach . In combination with vitamin C, for example from a glass of fruit juice, the absorption of the plant-based variant (non-heme iron) is further supported .
What are the signs of low iron levels? When supplies are low, the body can transport less oxygen through the blood . This can manifest itself in a feeling of weakness, rapid fatigue, pallor or increased sensitivity to cold. .
Can excess iron be harmful? Yes, because the body has no active excretion method for iron, large amounts can be toxic . In conditions such as hemochromatosis, excessive absorption leads to accumulation in the organs .
