Women’s iron needs throughout the life span

Women have unique health and nutritional needs. One nutrient of particular importance is iron, and it’s the most common nutrient deficiency globally that more commonly affects women [1]. Throughout the different life stages, there are several considerations that can affect women’s iron needs such as menstruation, pregnancy, childbirth, and menopause. Let’s take a look at how needs change throughout the lifespan!

First off, what is iron?

Iron is a mineral that the body needs for growth and development. It’s needed to transport oxygen around the body, store oxygen in our muscles, support immune function and provide us with energy.

Signs and Symptoms of Iron Deficiency

If our body doesn’t have enough iron, this can hinder our immune function, lead to a lack of oxygen making its way to our muscles and extremities, and leave us with little energy. This can cause a range of symptoms including fatigue, headaches, increased risk of infection, pale skin, weakness and dizziness, inability to concentrate, shortness of breath, cold hands and feet, and more. Clearly, iron is a very important nutrient for our health!

Iron Needs Throughout the Lifespan

 Teenage Years

 Girls typically reach puberty during their teenage years and begin menstruation. Iron needs increase at this age because of iron losses through menstruation blood. Girls aged 14-18 (assuming menstruation) are recommended to have 15mg of iron a day [2]. Those who have heavier periods can experience more iron losses and may be at increased risk of iron deficiency [3].

Adulthood

For women aged 19-50, iron needs are 18mg a day, which is more than double the recommended amount for men at 8mg a day [2]. Lifestyle factors can further influence iron needs, such as for women who are highly active [4]. When exercising, women can lose iron through sweat losses. Additionally, a hormone called hepcidin increases which is a peptide hormone produced in the liver. High hepcidin levels inhibit iron absorption in the intestine [5]. Certain sports like running can also increase iron needs due to foot-strike haemolysis, where repeated forceful impact of the feet to the ground can cause injury to blood cells in capillaries [6].

Women may also make certain lifestyle decisions that can impact iron needs, such as following a vegetarian or vegan lifestyle. While iron needs can be met on these diets, iron needs increase to 1.8x the recommended amount and women may require additional planning to reach these needs [7]. This is because the iron found in plant foods, called non-heme iron, isn’t as easily absorbed as the type of iron found in animal foods, called heme iron. Plant foods also contain phytates which can block iron absorption. For example, a menstruating woman following a vegan diet is recommended to have ~32mg of iron a day (18mg x 1.8).

 Pregnancy & Breastfeeding

 Some women may choose to fall pregnant. Iron requirements become even higher during pregnancy and breastfeeding as more iron is needed to support the developing fetus as well as the mother as the mother’s blood volume increases. Pregnant women are recommended to aim for 27mg of iron daily due to these increased needs [2]. As you can see, that’s quite a big jump from the 18mg recommended for menstruating women!

 How can you include enough iron?

Including more iron-rich foods in your diet can help to replace iron losses and help you meet higher iron needs. Animal sources of iron include lean meats, poultry, fish, eggs, and oysters. Plant sources of iron include iron-fortified cereals, soybeans, tofu, almonds, pumpkin seeds, lentils, soybeans, kidney beans and other legumes. 

Pairing non-heme sources of iron with heme sources of iron can help to boost absorption, such as pairing meat with beans [8]. For those who follow plant-based diets, pairing sources of iron with sources of vitamin C, such as citrus fruits, can help to boost absorption. Certain foods can inhibit iron absorption, such as tea and coffee, and having these drinks away from your meals can also help [8]!

Final Thoughts

Iron is a key nutrient for women to be aware of across their life span. A blood test can identify iron stores over time and can indicate if iron infusions or iron supplements may be needed to help restore iron levels. If you suspect you may have iron deficiency or are experiencing the symptoms listed above, we recommend getting your iron levels checked by your General Practitioner. As having too high levels of iron can also be dangerous, we recommend only taking supplements under the guidance of a health professional!

References

[1] Tang C, King K, Ross B, Hamad N. Iron deficiency in women: clearing the rust of silence. Lancet Haematol 2022. https://doi.org/10.1016/S2352-3026(22)00079-5.

[2] National Health and Medical Research Council, Australian Government Department of Health and Ageing, New Zealand Ministry of Health. Nutrient Reference Values for Australia and New Zealand. Canberra: National Health and Medical Research Council; 2006. Updated 2017.

[3] Mansour D, Hofmann A, Gemzell-Danielsson K. A Review of Clinical Guidelines on the Management of Iron Deficiency and Iron-Deficiency Anemia in Women with Heavy Menstrual Bleeding. Adv Ther. 2021 Jan;38(1):201-225. doi: 10.1007/s12325-020-01564-y. Epub 2020 Nov 27. PMID: 33247314; PMCID: PMC7695235.

[4] Alaunyte I, Stojceska V, Plunkett A. Iron and the female athlete: a review of dietary treatment methods for improving iron status and exercise performance. J Int Soc Sports Nutr. 2015 Oct 6;12:38. doi: 10.1186/s12970-015-0099-2. PMID: 26448737; PMCID: PMC4596414.

[5] Pagani A, Nai A, Silvestri L, Camaschella C. Hepcidin and Anemia: A Tight Relationship. Front Physiol. 2019 Oct 9;10:1294. doi: 10.3389/fphys.2019.01294. PMID: 31649559; PMCID: PMC6794341.

[6] Sim M, Garvican-Lewis LA, Cox GR, Govus A, McKay AKA, Stellingwerff T, Peeling P. Iron considerations for the athlete: a narrative review. Eur J Appl Physiol. 2019 Jul;119(7):1463-1478. doi: 10.1007/s00421-019-04157-y. Epub 2019 May 4. PMID: 31055680.

[7] Trumbo P, Yates AA, Schlicker S, Poos M. Dietary reference intakes: vitamin A, vitamin K, arsenic, boron, chromium, copper, iodine, iron, manganese, molybdenum, nickel, silicon, vanadium, and zinc. J Am Diet Assoc. 2001 Mar;101(3):294-301. doi: 10.1016/S0002-8223(01)00078-5. PMID: 11269606.

[8] Piskin E, Cianciosi D, Gulec S, Tomas M, Capanoglu E. Iron Absorption: Factors, Limitations, and Improvement Methods. ACS Omega. 2022 Jun 10;7(24):20441-20456. doi: 10.1021/acsomega.2c01833. PMID: 35755397; PMCID: PMC9219084.