Iron replacement therapy in women: scientific basis, indications and recommendations

Iron replacement therapy – often referred to as iron supplementation – plays a particularly important role in women, as they are more frequently affected by Iron deficiency than men. This article highlights the physiological basis of iron metabolism, common causes of Iron deficiency, diagnostic procedures and evidence-based recommendations for supplementation. Scientific studies and guidelines are used to provide a sound basis for practice and everyday life.

1. Introduction
Iron is an essential trace element that is particularly important for the formation of haemoglobin in the blood. Women of childbearing age are at increased risk of Iron deficiency due to monthly menstrual losses and increased requirements during pregnancy and breastfeeding. Untreated Iron deficiency can lead to anaemia, which manifests itself in symptoms such as fatigue, weakness, concentration problems and reduced performance. Evidence shows that targeted supplementation can improve iron status and sustainably increase quality of life.

2. Physiology and importance of iron
2.1 Function of iron in the body
Iron plays a central role in supplying oxygen to the tissues, as it is a component of haemoglobin and enables the transport of oxygen in the blood. It is also a component of myoglobin in the muscles and of various enzymes involved in energy metabolism processes. Adequate iron levels are therefore important for the entire organism.

2.2 Iron absorption and regulation
Iron is mainly absorbed in the upper jejunum (the upper part of the small intestine), whereby the duodenal epithelium (the layer of cells lining the inner wall of the duodenum) absorbs available iron via specific transport mechanisms such as the divalent metal ion transporter 1 (DMT1). Systemic regulation is significantly influenced by the hormone hepcidin, which controls absorption and release from stores depending on iron status. Low hepcidin levels promote iron absorption, while elevated levels cause a reduction in the event of excess.

3. Causes and risk factors for Iron deficiency in women
3.1 Menstrual iron loss
Regular menstrual cycles lead to recurrent blood loss. This can lead to a negative iron balance, especially in cases of heavy or prolonged menstrual bleeding.

3.2 Pregnancy and breastfeeding
During pregnancy, the need for iron increases significantly as blood volume increases and the foetus needs iron for its development. There may also be an increased need during breastfeeding, so targeted supplementation is advisable.

3.3 Eating habits
An unbalanced diet or vegetarian/vegan diets can lead to reduced intake of haem iron, which is more readily available in animal products than non-haem iron from plant sources. In addition, foods containing phytic acid (e.g. whole grains, legumes,
nuts and seeds) can inhibit iron absorption.

3.4 Other causes
In addition to the factors mentioned above, chronic diseases, inflammatory processes or gastrointestinal blood loss (e.g. due to ulcers) can also contribute to the development of Iron deficiency.

4. Diagnosis of Iron deficiency
4.1 Laboratory parameters
Iron deficiency is mainly diagnosed by determining the following laboratory parameters:

• Serum ferritin: provides an indication of iron stores. Low values indicate a deficiency.
• Serum iron and transferrin saturation: These parameters reflect the amount of circulating iron and the capacity of transferrin.
• Haemoglobin: a low haemoglobin level may indicate resulting anaemia.
  If functional Iron deficiency or inflammatory processes are suspected, additional markers such as C-reactive protein (CRP) can be used for interpretation.

4.2 Differential diagnosis
Particularly in cases of chronic inflammation or severe blood loss, a differential diagnosis should be made to rule out other causes of anaemia.

5. Evidence-based strategies for iron supplementation
5.1 Indications for supplementation
The indication for iron supplementation should be based on a careful diagnosis. Typical indications are:

• Biochemically confirmed Iron deficiency (low ferritin, low transferrin saturation)
• Iron deficiency anaemia with clinical symptoms
• Increased requirement during pregnancy and breastfeeding

5.2 Preparations and dosage forms
Iron preparations are available in various forms. The most commonly used are:

• Oral preparations: Examples include ferrous sulphate, ferrous glycinate and ferrous fumarate. These preparations differ in terms of bioavailability and tolerability. Ferrous sulphate is frequently used, but can cause gastrointestinal side effects such as nausea, constipation or diarrhoea.
• Intravenous iron supplementation: This method is chosen in cases where oral intake is insufficient (e.g. in cases of malabsorption, severe intolerance to oral preparations or when rapid correction of the deficiency is required).

PHYTOFERRIN +C | IRON capsules are an innovative product specially tailored to the needs of women with Iron deficiency. These capsules combine high-quality iron with valuable natural ingredients. Specifically, they contain:

• Buckwheat germ powder (Fagopyrum esculentum): in addition to iron, it also provides secondary plant substances that can contribute to general health.
• Rosehip extract (Rosa canina): known for its high vitamin C content and antioxidant properties, it also supports iron absorption.
• Calcium L-ascorbate: a well-tolerated form of vitamin C that not only promotes iron absorption but also supports the immune system.

This combination can be a useful dietary supplement, especially for women with increased iron requirements and accompanying nutrient deficiencies. The synergistic effect of the ingredients aims to optimise the bioavailability of iron while also achieving other health-promoting effects.

5.3 Dosage and application schedule
The dosage depends on the severity of the deficiency, body weight and the specific preparation. Studies show that partial dosing (e.g. every other day) can improve absorption, as excessive daily doses can lead to oversaturation of the transport mechanisms and increased side effects.

5.4 Factors influencing iron absorption

• Food components: Vitamin C (ascorbic acid) can significantly improve iron absorption, whereas coffee, tea, dairy products or calcium-rich foods inhibit absorption.
• Drug interactions: Some medications can impair iron absorption. It is therefore advisable to allow sufficient time between taking medication and iron supplementation.

6. Side effects and special considerations
6.1 Gastrointestinal tolerance
Gastrointestinal complaints are among the most common side effects of oral iron supplementation. To minimise these, it may be helpful to take the supplement with meals or to use sustained-release preparations.

6.2 Risk of iron overload
Uncontrolled and long-term use of iron preparations without a predominant clinical need can lead to iron overload. This is particularly important to note in genetic disorders such as haemochromatosis.

6.3 Special patient groups
The prevention of Iron deficiency is particularly important in pregnant women. National and international guidelines therefore recommend prophylactic iron supplementation, taking into account individual risk factors and laboratory parameters.

7. Summary and conclusion
Iron supplementation in women is an evidence-based procedure used to treat and prevent Iron deficiency and the resulting anaemia. The specific characteristics of female iron levels, due to menstrual losses and increased demands during pregnancy, require individual assessment and treatment planning. The choice of dosage form (oral or intravenous), the dosage and consideration of interactions and side effects are crucial factors that contribute to successful therapy.

A sound diagnostic approach and the selection of a suitable preparation – such as PHYTOFERRIN +C | IRON capsules – can help to effectively improve iron status and thus contribute to a sustainable increase in quality of life.

References

1. WHO (World Health Organisation):
Guidelines on Iron deficiency anaemia and recommendations for iron prevention.
2. Zimmermann, M. B. & Hurrell, R. F. (2007):
"Nutritional Iron deficiency." The Lancet, 370(9586), 511–520.
3. Camaschella, C. (2019):
"Iron deficiency." Blood, 133(1), 30–39.
4. National care guidelines, e.g. for the treatment of Iron deficiency anaemia during pregnancy.