Iron is present within many foods (many more than red meat alone!) – but it’s not easily absorbed by the body. This means it can be difficult to meet our requirements of this essential mineral. In fact, iron deficiency is among the most common nutritional deficiencies, worldwide. If you struggle with iron, you’re not alone – find our guide to boosting iron intake and absorption, below.
Why is iron so important?
Iron plays an essential role in delivering oxygen throughout the body, via a protein known as haemoglobin, in the blood. It also critically supports immune function and energy production. Perhaps a lesser-known function of iron is its role in the production and function of multiple neurotransmitters, including serotonin (the ‘happy hormone’), dopamine (the ‘reward chemical’) and noradrenaline (which regulates attention, cognition, and stress responses).
Adequate stores of ferritin (the storage form of iron) are particularly important during stages of rapid growth and development, and following blood loss. This includes:
- Children
- Adolescents
- Menstruating women
- Women who are trying to conceive, or pregnant.
During pregnancy, it’s important – as much as possible – to address iron depletion or deficiency, promptly. To prevent deficiency during pregnancy, preconception care will ideally focus on building adequate iron stores. This is because the increased blood supply, placenta and unborn baby all increase maternal demand for iron. Moreover, the unborn baby can store a six to eight month supply of iron during the latter stages of pregnancy, if maternal supply is adequate.
Signs and symptoms of iron deficiency
If you’re experiencing any of the following, it’s worthwhile checking in with your GP to organise a blood test to check iron studies, along with any further investigations as required:
- Fatigue, lethargy and weakness
- Pallor (pale or ‘washed out’ complexion)
- Dizziness
- Poor concentration
- Frequent illness
- Shortness of breath and heart palpitations, particularly during exercise
- Hair loss
- Brittle nails
Dietary sources of iron
There are two forms of dietary iron:
- Haem iron (from animal-based sources; better-absorbed by the body) – found in large amounts in red meats including beef, lamb and organ meats like liver; also found in poultry, fish and shellfish such as oysters.
- Non-haem iron (mostly from plant-derived foods; less well-absorbed by the body) – found in eggs, legumes, firm tofu, wholegrains, nuts, seeds, dried apricots and dark green leafy vegetables including kale, spinach and broccoli.
Compared to haem iron, non-haem iron is less bioavailable, meaning that it is less well-absorbed by the body. However, in most diets, the majority of iron is sourced from plant-derived foods. Certain dietary strategies can aid non-haem iron absorption, which is pretty amazing!
To aid iron absorption:
- (If you’re able to) consume non-haem sources of iron with meat or fish.
This might look like:
- Serving a chickpea ragu alongside some slow-cooked lamb.
- When eating out, ordering a side of leafy greens to accompany a main dish containing meat or fish.
- Spread your intake of dietary iron over the course of day.
This might look like:
- Enjoying a variety of wholegrains, nuts and seeds in granola at breakfast,
- Adding one cup of lentils to a salad at lunch, and
- Serving stir-fried lean beef and leafy greens with quinoa or brown rice for dinner.
- Enjoy sources of non-haem iron with vitamin C rich foods.
This might look like:
- Topping granola with sliced kiwi fruit and strawberries.
- Adding cherry tomatoes and a salad dressing of lemon juice and extra-virgin olive oil to a lentil salad.
- Incorporate a two-hour interval between dietary sources of non-haem iron and tannin-rich foods and drinks, such as coffee and tea.
This might look like:
- Starting your day with a glass of water and a balanced breakfast, and saving your coffee or tea until you arrive at work.
- Separate dietary sources of calcium (such as cow’s milk) and iron supplements, as calcium can impair absorption of iron supplements.
Do I need a supplement?
Iron supplementation is an effective tool for restoring low or suboptimal ferritin stores to within healthy range. It’s incredibly helpful during times of increased demand for iron, such as preconception and pregnancy. Where iron levels are very low, an infusion may be needed instead.
Overdosing on iron can result in toxicity, so – as with all supplements – it’s important not to self-prescribe. Certain forms of iron are also better tolerated and less likely to cause gastrointestinal upset, including constipation. If you’re unsure, consult an Accredited Practising Dietitian for support.
For expert dietary support to support you on your personal health journey, book your first appointment with one of our wonderful Accredited Practising Dietitians today.
Written by Caitlin Branch, Student Nutritionist, and Amanda Smith, Accredited Practising Dietitian.
References
Berthou, C., Iliou, J. P., & Barba, D. (2021). Iron, neuro-bioavailability and depression. EJHaem, 3(1), 263-275. https://doi.org/10.1002/jha2.321
Braun, L., and Cohen, M. (2017). Essential herbs and natural supplements. Elsevier Australia.
Brown, J. (2020). Nutrition through the life cycle (7th ed.). Cengage Learning, Inc.
Food Standards Australia and New Zealand. (2021). Foods that contain: Iron (Fe). Australian Food Composition Database. https://www.foodstandards.gov.au/science/monitoringnutrients/afcd/Pages/foodsbynutrientsearch.aspx?nutrientID=FE
World Health Organization. (2023). Micronutrients. https://www.who.int/health-topics/micronutrients#tab=tab_1