food sources of iron

What foods contain iron?

We all need iron. It’s an essential mineral which plays a key role in transporting life-giving oxygen around the body, among other important functions.

However, many people experience low iron levels. In fact, it’s the most common nutritional deficiency in the world. 1

Learn all about iron and how you can get enough of it here.

What is iron and why do we need it?


Iron makes up a key part of the protein haemoglobin, which helps make up our red blood cells.

Haemoglobin is also what gives blood its red colour and is made from two main components – one of which is iron.2

Iron contributes to normal oxygen transport around the body

Haemoglobin acts as a vehicle for oxygen, carrying oxygen particles from the lungs to all the cells in the body.3 When we get sufficient iron through our diet, we are able to make plenty of haemoglobin. Running low on iron means that your body can’t make as much haemoglobin – and subsequently, can’t carry as much oxygen to your body’s cells.

Iron contributes to energy yielding metabolism

Iron also helps us in the process of converting food to energy. So, without iron, our bodies can’t produce energy properly.4

Iron contributes to the normal function of the immune system

Iron is also involved in our immune response, with lower iron levels is associated with an increased risk of ill-health.5

Symptoms of low iron and iron deficiency anaemia

The main signs to look out for which might indicate you are low on iron are:6
  • tiredness and lack of energy
  • shortness of breath
  • heart palpitations (where you can feel your heart beating and it might feel irregular)
  • a pale complexion

A GP can diagnose iron deficiency anaemia with a blood test. Luckily, it’s easily treated by increasing your intake of iron.

This is usually done either through foods or supplementation, which your GP will advise you on.

Where to find iron


Foods

Iron is an abundant mineral, found naturally in many foods. The most bioavailable food sources of iron include:7 8
  • meat – the most plentiful and easily absorbed source of iron found in nature is in meat such as beef and chicken live
  • fish such as sardines
  • oysters, clams and other seafood

Vegetarian and vegan sources of iron include:

  • beans such as red kidney beans, chickpeas and black bean
  • lentils
  • soy products such as tofu and tempeh
  • nuts – especially pistachios, cashews, walnuts and pine nuts
  • seeds – like pumpkin seeds, linseeds and sesame seeds
  • leafy green vegetables – for example spinach, broccoli, kale and swiss chard
  • dried fruit – including apricots, prunes, raisins and dates
  • eggs
  • oats
  • dark chocolate
Our ability to absorb iron from a vegetarian source is less effective than from an animal source. However, absorption can be enhanced by including a source of vitamin C with the iron-rich plant-based food.9

For example, adding red peppers, tomatoes or fresh fruit will allow you to get the most out of the sources of iron in food you’re consuming.

It’s important to note that drinking tea or coffee with a meal also inhibits the absorption of iron, so avoid these beverages with meals or snacks.10 Many people top up their iron supplies with fortified foods. Fortified foods are those which have had iron added to them. These include many breakfast cereals, and in the UK, all white and brown flour is fortified with iron.11

Easy iron-rich snack ideas 

  • hummus and red pepper or carrot sticks
  • handful of almonds with an apple
  • a small piece of dark chocolate with a handful of blueberries
  • sprinkle pumpkin seeds over porridge
  • a few dried apricots with almonds
  • a small bowl of edamame beans with a squeeze of lemon juice

How much iron do we need?

The NHS recommends:12 13

For infants:

  • 0-3 months - 1.7 mg
  • 4-6 months - 4.3 mg
  • 7-12 months - 7.8 mg
  • 1-3 years - 6.9 mg

For children:

  • 4-6 years - 6.1 mg
  • 7-10 years - 8.7 mg

For teenagers:

  • males 11-18 years - 11.2 mg
  • females 11-18 years - 14.5 mg

For adults:

  • males over 18 years- 8.7mg
  • females aged 19 to 50 - 14.8mg
  • females over 50 - 8.7mg
Infants up to the age of 1 should get all their iron from either breast milk or infant formula. In the UK, all infant breast-milk substitutes are fortified with iron to a typical level of 6–7 mg per litre.14

Who might be low on iron?

Iron deficiency – known as iron deficiency anaemia – is very common. It’s thought to affect around 25% of the world’s population. People in developed countries such as the UK tend to be less likely to have low iron levels due to access to nutritious foods.15

However, it’s still relatively common in the UK.

Reasons why someone might become deficient in iron include:

  • Vegan or vegetarian - many vegan and vegetarian sources of iron are available, but iron from plant sources tends to be lower in amount and is less easily absorbed than meat sources.

  • Highly restricted diet – extreme weight loss diets or fasts can result in low iron levels and are not recommended generally.

  • Pregnancy – iron requirements are naturally higher during pregnancy as iron is needed for the developing foetus.16 Therefore, pregnant women can run low on iron unless they up their intake.

  • Menstruation – losing blood through a monthly period can cause low iron levels, especially if they’re heavy.

  • Age and gender - according to the British Nutrition Foundation, 48% of girls aged 11 – 18 have low iron levels.17

Is it possible to get too much iron?


Yes. As vital iron is to the functioning of the body, we only need it in small amounts.

If we get too much iron, it can be bad for us. 20mg per day is considered too high a dose to have regularly.18

It’s unlikely that someone would get too much iron through their diet, unless you’re regularly eating large amounts of red meat.

A healthy body can control the amount of iron absorbed into the blood and ensure there is no build-up. However, this system of regulation can sometimes go wrong and the result can be a build up of iron in the body. This is called haemochromatosis and is relatively rare.19

More commonly, iron overload is caused by ingesting too much via iron supplements. If you’re not a vegan, pregnant woman, menstruating woman, or have a condition such as IBD and are eating a balanced diet including iron-rich foods, you’re unlikely to need an iron supplement.

Symptoms of too much iron include:20
  • stomach pains
  • nausea
  • vomiting
  • constipation

These symptoms should stop quickly once you reduce your iron intake below 20mg.

Last updated: 01 July 2020

Sources
  1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3685880/
  2. https://www.nhs.uk/conditions/red-blood-count/
  3. https://courses.lumenlearning.com/wm-biology2/chapter/transport-of-oxygen-in-the-blood/
  4. https://academic.oup.com/jn/article/148/suppl_1/1001S/5033576
  5. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3085559/
  6. https://www.nhsinform.scot/illnesses-and-conditions/nutritional/iron-deficiency-anaemia
  7. https://www.nhsinform.scot/illnesses-and-conditions/nutritional/iron-deficiency-anaemia
  8. http://www.wales.nhs.uk/sitesplus/documents/866/iron_food_fact_sheet%20BDA.pdf
  9. http://www.icppharm.com/News-Resources/Articles/Effects-of-Vitamin-C-on-Iron-Absorption.aspx
  10. https://www.nhs.uk/conditions/iron-deficiency-anaemia/
  11. https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/339309/SACN_Iron_and_Health_Report.pdf
  12. NHS Children’s Section – Iron Content of Food Trust Docs ID: 118 Author: Paediatric Dietitians Date Reviewed: 13/02/2018
  13. https://www.nhs.uk/conditions/vitamins-and-minerals/iron/
  14. https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/339309/SACN_Iron_and_Health_Report.pdf
  15. https://pubmed.ncbi.nlm.nih.gov/11943635/
  16. https://www.nhs.uk/news/pregnancy-and-child/iron-pills-in-pregnancy-make-babies-healthier/
  17. https://www.nutrition.org.uk/attachments/article/546/Iron%20deficiency%20anaemia%20and%20school%20children%20(2).pdf
  18. https://www.nhs.uk/conditions/haemochromatosis/
  19. https://www.nhs.uk/conditions/vitamins-and-minerals/iron/
  20. https://www.nhs.uk/conditions/vitamins-and-minerals/iron/
AnaemiaFood & DrinkIronMinerals