Nutrient deficiency seems out of place when living in a country where there is a wealth of food available. But while people generally get enough of most vitamins and minerals for good health, there are a number of micronutrients (‘micro’ meaning small – including vitamins, minerals and other chemicals) that many are lacking. One of these is iron.
Iron deficiency is the most common nutrient deficiency across the globe. Left untreated, it may lead to anaemia, a condition where the level of red blood cells or haemoglobin in the body is lower than normal. As red blood cells carry oxygen around the body, having anaemia can take a toll on the body because oxygen levels are decreased. Added strain is placed on the heart because it needs to pump harder to convey enough oxygen around the body, which can lead to arrhythmia, an enlarged heart or heart failure. It's estimated that 30% of the world’s population is anaemic primarily due to iron deficiency.1
A common side effect of our busy lifestyles of working, running households, raising children, keeping active and so on is fatigue. You may be tired from burning the candle at both ends, or there may be something else going on. If you’re feeling noticeably fatigued or run down, it may be due to your iron levels.
But don’t self-diagnose. It’s always best to get a blood test, check your levels and then see a dietitian before taking any vitamin or mineral supplement. If you’re going to pay money to bridge a ‘nutritional gap’ in your diet, you may as well be sure that you need to. Taking iron supplements if you’re feeling overly tired or fatigued will do no good if the problem isn’t low iron stores.
In the meantime, you can take stock of your diet and make sure that as well as eating healthily overall, you’re getting enough iron to meet your body’s needs.
All about iron
Iron is not a very bio-available mineral. This means that it’s not easily absorbed by the body. In fact, at its best bio-availability, we only ever absorb up to 25% of the iron that actually goes in our mouths.
The Recommended Dietary Intake (RDI) for iron is 8mg for men and 18mg for women of childbearing age (or who are menstruating). If you’re pregnant, this recommendation increases to 27mg per day.2 The RDI takes into account the fact that only a small amount of the iron we eat is actually absorbed by the body, so don’t try to take in more than this unless instructed to do so by your doctor.
Heme iron vs non-heme iron
The iron from our diets comes in several forms known as heme and non-heme.
Heme iron comes from animal food sources, such as beef, pork, lamb, seafood, kangaroo, other game and poultry. The iron in these foods is present as haemoglobin and myoglobin, hence the name ‘heme iron’.
Non-heme iron is the form of iron that comes from all other food sources. Plant-based sources, such as spinach, dark green leafy vegetables, kidney beans, other legumes and sesame seeds, are non-heme sources of iron. Other non-heme sources are foods that have been enriched or fortified with iron, such as breakfast cereals and drink bases. The iron from non-heme sources is less bio-available. This means that due to a variety of different factors, the iron in these foods is not easily absorbed by the body.
Pumping up iron absorption
1. Maximise your intake of heme iron sources
Iron from heme iron sources is much more bio-available and is the most easily absorbed by your body.
Aim to include red meat 2–3 times a week, chicken or turkey 2–3 times per week and some kind of seafood 2–3 times per week, and you’ll be doing pretty well. If you’re a vegetarian or vegan, you may need to seek advice from a dietitian and have a personalised eating plan drawn up to help you meet your body’s iron needs from non-heme iron.
2. Include vitamin C rich foods with both your heme and non-heme iron sources
When eaten at the same time, vitamin C enhances the absorption of iron from your meal. Foods that are high in vitamin C include most fruits and vegetables, especially broccoli, Brussels sprouts, red capsicum, oranges, strawberries, kiwi fruit, tomatoes, lemons and limes.
Recipe tip: an example meal following this principle would be barbecued lamb chops on a lentil puree, topped with a tomato salsa. Serve with wilted baby spinach and steamed broccoli drizzled with olive oil and lemon juice.
3. Be mindful of foods that decrease iron absorption
Foods that contain phytates and phenols decrease the absorption of non-heme iron. These are foods generally high in fibre like wholegrains and cereals. It’s important to eat fibre, so don’t cut these foods from your diet. Simply eat them at other times throughout the day, or make sure that you are eating plenty of foods containing heme iron and you’ll be fine.
Tea and coffee also contain substances that decrease iron absorption, so avoid drinking them at meal times.
- World Health Organisation; Micronutrient deficiencies; www.who.int/nutrition/topics/ida/en/
- Australian Government National Health and Medical Research Council; Nutrient Reference Values for Australia and New Zealand www.nrv.gov.au/nutrients/iron
About the author
The Healthy Eating Hub
This article was written by an Accredited Practicing Dietitian from The Healthy Eating Hub. The Healthy Eating Hub is a team of university-qualified nutritionists and dietitians who are passionate about helping people develop long term healthy eating habits through offering evidence-based and practical nutrition advice that people can put into practice straight away.