Why is Iron so important, particularly for women?

Why is Iron so important, particularly for women?

Iron has a variety of important roles in your health and wellbeing, and one of its key functions is in developing red blood cells which carry oxygen around your body.  It is also an essential component in many enzyme reactions and helps your immune system function at its best.

In adults, around 70% of the body’s Iron is found in haemoglobin molecules in red blood cells that enable oxygen to be carried in your blood from your lungs to the tissues, so it plays a vital role in humans.

Am I getting enough Iron?

Research shows the average dietary intake of Iron is lower among women than men.  Over a quarter (27%) of women aged 19-64 years and almost half (48%) of girls (aged 11-18 years) may have an inadequate intake of Iron.

In comparison, just 1% of adult men and 9% of teenage boys are likely to have an inadequate intake of Iron.

See what your diet's missing. Create your free Diet Profile.

Symptoms of Iron deficiency

When your body doesn’t have enough Iron, your blood will lack adequate healthy red blood cells which carry oxygen to the body’s tissues.  Some of the common symptoms of Iron deficiency include tiredness, shortness of breath, noticeable heartbeats (heart palpitations) and pale skin. 

Iron deficiency anaemia can be caused by blood loss from the stomach and intestines, which may be due to stomach ulcers, piles, inflammatory bowel disease or taking non-steroidal anti-inflammatory drugs such as ibuprofen and aspirin. (4)  

Blood loss due to heavy periods is the most common cause of Iron deficiency in women of childbearing age. 

You can learn about the different dietary sources of Iron in our Vitamins and Minerals section here

Why women are more at risk of Iron deficiency

Menstrual periods and Iron

Heavy periods (also known as menorrhagia), are a common complaint among women.  The prevalence increases with age, peaking in women aged 30-49 years.  1 in 20 women aged 30-49 years in the UK consult their GP each year about heavy periods.

It is difficult to measure blood loss accurately, and the perception of what is ‘heavy’ menstrual bleeding is subjective.  In some studies assessing menstrual blood loss, the prevalence of heavy periods ranged from 20-52% based on subjective assessment.  Periods are considered ‘heavy’ if they are interfering with a woman’s quality of life and causing problems.

You may also like to read Nutrition for PMS 

Pregnancy and Iron

There are no recommendations for increasing Iron intake during pregnancy as the extra demand should be met from existing body stores and lack of menstrual blood loss.

It is also thought that a woman’s body when pregnant, and breastfeeding, adapts to ensure the baby receives adequate supply of Iron, even when the mother is Iron deficient.  However some pregnant women may develop low Iron status so plenty of Iron-rich foods should be eaten.  You can learn more about Iron rich foods here.

It can take several months for a woman to replenish her Iron stores after a pregnancy and some studies suggest leaving a gap of 18 months between pregnancies to enable nutrient stores to replenish. (2,7)

Read our blog Is it safe to go plant-based while pregnant.

How much Iron do I need?

Men and women have different requirements for Iron.  From the onset of menstruation until monthly periods stop, after the menopause, women need almost twice as much Iron as men. This is because a woman's monthly period can use up the body’s Iron reserves, especially if dietary Iron is low or if a woman has heavy periods. 

The Recommended Nutrient Intake (RNI) for children aged 7-10 years is 8.7mg a day.  The adolescent growth spurt leads to an increase in blood volume, haemoglobin and muscle tissue, so iron requirements also increase. The RNI is 11.3mg a day for boys and 14.8mg a day for girls aged 11-18 years.(2)

Among adults (aged 19-50 years) the RNI is 8.7mg a day for men and 14.8mg a day for women.  From age 50+ years requirements for both men and women are the same, with the RNI of 8.7mg a day.(2)


Discover our range of vegan vitamins and supplements.

You may also like to read: 10 practical tips to reduce bloating

Want to hear more from our nutritionists? Sign up to our email newsletter for insights and exclusive offers: 




  1. EU Register of nutrition and health claim made on foods (2016). Available: https://ec.europa.eu/food/safety/labelling_nutrition/claims/register/public/?event=register.home
  2. SACN (2010) Iron and Health. Available: https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/339309/SACN_Iron_and_Health_Report.pdf
  3. NDNS (2018) NDNS results from years 7 and 8 (combined). Available: https://www.gov.uk/government/statistics/ndns-results-from-years-7-and-8-combined
  4. NHS Choices (2018) Iron deficiency anaemia. Available: https://www.nhs.uk/conditions/iron-deficiency-anaemia/
  5. NICE (2018) Menorrhagia. Available: https://cks.nice.org.uk/topics/menorrhagia/
  6. Lethaby et al (2015) Progesterone or progestogen-releasing intrauterine systems for heavy menstrual bleeding. Available: https://pubmed.ncbi.nlm.nih.gov/25924648/
  7. BNF (2013). Nutrition and Development: short and long-term consequences for health. Available: https://www.nutrition.org.uk/attachments/599_Q_A%20chapter.pdf