by Michaela Carrick, BSc Human Nutrition
What is iron?
Iron is a mineral needed by your red blood cells, the cells that carry oxygen around the body in your blood (1). Dietary Iron can be found in a variety of foods such as red meat, beans, lentils, dark green leafy vegetables, nuts, dried fruits, and fortified foods (e.g. breakfast cereals with added iron).
What is Iron deficiency anaemia?
If you don’t get enough iron from your diet, you may develop iron deficiency anaemia. Haemoglobin is a protein that carries oxygen in your blood. If you have iron deficiency, you will have less haemoglobin in your red blood cells. This means less oxygen that can be transported around your body (1).
Signs of mild iron deficiency include:
- Tiredness
- Pale skin
Iron also plays an essential role in the immune system, so you may become ill more often if you have an iron deficiency (2).
Signs of severe iron-deficiency anaemia include:
- Brittle nails
- Hair thinning or loss
- Itchy skin
- Mouth ulcers or scars
- Heart palpitations
In the UK, young children, teenage girls, women of childbearing age, and older adults are most at risk of developing iron-deficiency anaemia (3). Women are more at risk of anaemia than men due to the blood and iron lost during menstruation.
Haem vs non-haem iron
The iron in food can come in two different forms: haem iron and non-haem iron.
Both forms are useful to include in your diet to reach your body’s iron needs. Haem iron is better absorbed by your body than non-haem iron, with 15-30% of the haem iron in food being absorbed (4).
Haem iron is found mainly in animal foods such as:
- Red meat, especially liver
- Fish like tuna, sardines, and shellfish
- Chicken and other poultry
Non-haem iron is absorbed poorly by your body, with only 1-20% of the non-haem iron in food being absorbed (4). Non-haem iron is found mainly in plant foods.
Good sources of non-haem iron include:
- Tofu
- Dried apricots
- Nuts
- Beans and lentils
- Dark green leafy vegetables like broccoli, kale, and spinach
- Fortified foods like breakfast cereals and bread*
*All bread (except wholemeal) sold in the UK is fortified with iron, meaning extra iron is added.
How much iron do you need?
The amount of iron your body needs each day depends on your age and sex (5). Men and post-menopausal women need to consume 8.7mg iron daily. Women pre-menopause need 14.8mg daily to make up for the losses during menstruation. However, diet surveys have shown that many women in the UK do not eat enough iron to meet their body’s needs (6).
How can you prevent iron deficiency anaemia?
Including a variety of food sources of haem and non-haem iron in your diet can help you reach your body’s daily needs. However, there are also things you can do to improve how much non-haem iron can be absorbed by the body.
Here are our top tips:
- Vitamin C can increase non-haem iron absorption if your iron levels are low, so try pairing non-haem iron sources with sources of vitamin C (4). Foods containing vitamin C include citrus fruits, peppers, berries, leafy green vegetables, and potatoes. You can try squeezing lemon juice over kale or spinach based salads, having a glass of orange juice with your fortified cereal at breakfast, or including peppers in a tofu stir-fry.
- Avoid drinking tea or coffee with your iron-containing meals. The tannins in tea and coffee can limit non-haem iron absorption (7).
- Haem iron can increase absorption of non-haem iron so try eating sources of both in the same meal. For example, try a chicken and broccoli bake, grilled fish with mushy peas, or a beef stew with lentils.
Do you need a supplement?
If you are experiencing any signs or symptoms of iron deficiency, it is best to speak with a healthcare professional like your GP. A simple blood test can confirm if you are anaemic. Your GP may prescribe iron supplements for about six months if your blood iron levels are low.
References
1. Abbaspour N, Hurrell R, Kelishadi R (2014) Review on iron and its importance for human health. Journal of research in medical sciences: the official journal of Isfahan University of Medical Sciences. 19(2):164.
2. Failla ML. Trace elements and host defense: Recent advances and
continuing challenges. J Nutr 2003;133:S1443-7.
3. Public Health England (PHE), 2011, Scientific Advisory Committee on Nutrition (SACN) report, Iron and Health.
4. Hurrell R, Egli I. Iron bioavailability and dietary reference values. Am J Clin Nutr 2010;91:1461-7S.
5. Department of Health (DH), 1991, Dietary Reference Values. HMSO, London.
6. Public Health England (2020) NDNS 2020, Results from the National Diet and Nutrition Survey rolling programme for 2016 to 2017 and 2018 to 2019 for food consumption, nutrient intakes and nutritional status.
7. Delimont NM, Haub MD, Lindshield BL. The impact of tannin consumption on iron bioavailability and status: A narrative review. Current developments in nutrition. 2017 Feb 1;1(2):1-2.
