Iron in women’s diets – what do you need to know?

In the 18th century, French scientists observed in the laboratory that blood contains significant amounts of certain elements, including iron. It has since been proven that iron contributes to the proper production of red blood cells and haemoglobin, the protein responsible for transporting oxygen in the blood. For women, this issue requires particular attention, as iron metabolism is affected by menstruation, pregnancy, breastfeeding, age, diet and general health.

1. Properties of iron
2. What should you bear in mind?
3. Iron requirements for women
4. Pregnancy
5. An iron-rich diet

Properties of iron

Iron is a mineral element required primarily for the proper formation of red blood cells and haemoglobin (a protein) which binds oxygen in the lungs and transports it to the tissues. Iron is also found in myoglobin, a protein present in muscles that plays a role in the storage and transfer of oxygen within muscle tissue. For this reason, an adequate iron intake is important not only for haematological parameters (related to the haematopoietic system), but also for combating feelings of fatigue. Iron is also required for processes related to energy metabolism in the body, the proper functioning of the immune system, and normal cognitive function.

What should you bear in mind?

For women, it is particularly important to note that regular menstrual bleeding involves cyclical blood loss, and with it, a certain amount of iron. This loss varies from person to person, which is why nutritional requirements may differ between women of similar age but with different menstrual patterns, levels of physical activity, body weight, dietary patterns and iron stores. Particular attention should be paid to this nutrient by menstruating women, pregnant women, those on diets that severely restrict animal products, people with low energy intake, and women who train intensively, as in these situations it is easier for the intake to fall short of the body’s actual needs.

"Ascorbic acid (vitamin C) increases iron absorption, which supports the normal production of red blood cells and haemoglobin, as well as the transport of iron within the body" Łukasz Domerack – Dietitian

Iron requirements for women

Iron requirements vary depending on a woman’s stage of life. According to the nutritional guidelines for the Polish population, the recommended daily iron intake for adult women aged 19–50 is 18 mg, which is mainly due to menstruation and cyclical blood loss. After the age of 50, when most women no longer menstruate, the recommended intake is lower, at 10 mg per day – the same as for adult men. However, the guidelines alone do not tell the whole story about a woman’s actual situation, as factors such as iron stores prior to pregnancy, the heaviness of periods, previous births, diet, gastrointestinal conditions, medication, physical activity and laboratory test results also play a role.

Pregnancy

Pregnancy is a special period during which the recommended iron intake increases to 27 mg per day, as a woman’s body increases her blood volume, produces a larger pool of red blood cells and must meet the needs of the developing foetus and placenta. During lactation, the recommended intake is usually lower than during pregnancy and stands at 10 mg per day, partly due to the frequent absence of menstruation in the early stages of breastfeeding and the relatively low iron content in breast milk.

EFSA’s European dietary reference values for iron

* EFSA assumes that increased iron absorption and the body’s iron stores usually cover the additional requirements during pregnancy and lactation; therefore, the European reference values remain the same as for pre-menopausal women.

In addition, the European Nutrient Reference Value (NRV) used in the labelling of food and food supplements is 14 mg of iron per day.

An iron-rich diet

The amount of iron obtained from the diet is influenced not only by the choice of specific foods, but also by the form of the element and the composition of the meal as a whole. Sources of iron include meat, offal, fish, pulses, and certain seeds and nuts. Animal products mainly contain haem iron, which is easily utilised by the body, whereas plant-based products are dominated by non-haem iron, which has lower bioavailability.

For this reason, the iron content of a product alone does not always accurately reflect how much of this nutrient the body will actually utilise. The absorption of non-haem iron can be enhanced by vitamin C, whilst it may be reduced by phytates found in cereals and pulses, polyphenols in coffee, tea and cocoa, and large amounts of calcium consumed in the same meal.

Sources:

• Lynch, S., Pfeiffer, C. M., Georgieff, M. K., Brittenham, G., Fairweather-Tait, S., Hurrell, R. F., McArdle, H. J., & Raiten, D. J. (2018). Biomarkers of Nutrition for Development (BOND)-Iron Review. The Journal of nutrition, 148(suppl_1), 1001S–1067S. https://doi.org/10.1093/jn/nxx036
• Arosio, P., Cairo, G., & Bou-Abdallah, F. (2025). A Brief History of Ferritin, an Ancient and Versatile Protein. International Journal of Molecular Sciences, 26(1), 206. https://doi.org/10.3390/ijms26010206
• Briguglio, M., Hrelia, S., Malaguti, M., Lombardi, G., Riso, P., Porrini, M., Perazzo, P., & Banfi, G. (2020). The Central Role of Iron in Human Nutrition: From Folk to Contemporary Medicine. Nutrients, 12(6), 1761. https://doi.org/10.3390/nu12061761