Iron deficiency sneaks up on you. Here's how much you actually need — and whether your diet is cutting it close.
Follow iron from the plate to the bloodstream in six short steps. Swipe or tap Next.
Iron in food comes as haem or non-haem. Meat, fish and poultry can contain both; grains, legumes and vegetables contain non-haem iron only.[1]
Haem iron is absorbed more readily. Its absorption is estimated at 15–35%, while non-haem iron is usually much less well absorbed.[2]
As food is digested, iron is released and carried on into the small intestine. Most dietary non-haem iron is in the ferric (Fe³⁺) form.[4]
Absorption happens mainly in the duodenum and upper jejunum, the first stretch of the small intestine.[4,7]
The DMT1 transporter takes up ferrous iron (Fe²⁺), so non-haem Fe³⁺ is first reduced, by a membrane enzyme and by dietary reducing agents such as vitamin C.[4,6]
Haem iron enters by a separate route (exactly how is still being worked out), and its iron is released inside the cell.[8]
Inside the gut cell, iron is either stored in ferritin or exported through ferroportin into the blood, where transferrin carries it.[6,7]
When the cell’s own iron is high, it takes up less through DMT1 and stores more as ferritin.[7]
The liver makes hepcidin. It binds ferroportin and marks it for breakdown, so less iron leaves the gut cell for the blood.[5]
The body has no physiological way to excrete iron, so balance is controlled at absorption.[2] Most daily iron is recycled from old red blood cells; roughly 1–2 mg a day is absorbed from food to cover losses.[5]
Tap a factor to see how it tends to change the amount of iron getting through the doorway.
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Vitamin C and organic acids such as citric, lactic and malic acid can increase non-haem iron absorption.[1]
Meat, fish or poultry eaten in the same meal can increase non-haem iron absorption from plant foods.[1]
Polyphenols in tea, coffee and some herbal teas reduce non-haem iron absorption. In a single-meal study, polyphenol-rich drinks cut absorption from a bread meal by about half or more.[3]
Phytate, found in legumes, rice and other grains, is a major inhibitor of non-haem iron absorption[2]; NHMRC notes it can affect haem iron too.[1]
Calcium can reduce absorption of both haem and non-haem iron.[1]
The animation shows which way each factor pushes, not how much. Effects are clearest in single-meal studies; across a varied diet they are more modest, and a person’s own iron status generally matters more than diet composition.[2]
Sources reviewed November 2026. The diagram is a simplified schematic and is not to scale.
General information only, not medical advice. For questions about your own iron levels, symptoms or supplements, speak with your GP or pharmacist.
Your body runs on oxygen — and haemoglobin, the protein in red blood cells, is what carries it to every cell. Iron is what makes haemoglobin work. No iron means your cells run short of oxygen, and that's why fatigue is usually the first sign something's off.
Oxygen transport: Iron is a key component of haemoglobin, the protein in red blood cells that carries oxygen from your lungs to every cell in your body.
Energy production: Energy is literally iron-dependent — your cells need it to produce energy. Low iron shows up as fatigue, brain fog, and feeling wiped out after normal activity.
Immune function: Your immune system needs iron to fight infections effectively.
Brain function: Iron supports cognitive development and function, particularly important for children and adolescents.
Iron deficiency is the most common nutritional deficiency worldwide and is particularly prevalent in Australia among women of reproductive age, pregnant women, young children, and vegetarians.
Haem iron (from animal sources — better absorbed):
Red meat (beef, lamb, kangaroo) is the richest source. Chicken, pork, and fish also contain haem iron. Liver and other organ meats are extremely iron-rich but are very high in vitamin A, which is relevant in pregnancy; a GP, midwife or dietitian can discuss pregnancy food guidance. Oysters, mussels, and sardines are also excellent sources.
Non-haem iron (from plant sources — less well absorbed):
Legumes (lentils, chickpeas, kidney beans), tofu and tempeh, dark leafy greens (spinach, kale, silverbeet), iron-fortified breakfast cereals, wholegrain breads, nuts and seeds (especially pumpkin seeds and cashews), and dried fruits (apricots, figs).
Tips to improve absorption:
Vitamin C (citrus, capsicum, tomatoes) eaten with iron-rich foods increases absorption. Tannins in tea and coffee reduce iron absorption when consumed with meals. Cast iron cookware can leach small amounts of iron into food. Soak and sprout legumes and grains to reduce phytates that block absorption.
Iron deficiency develops gradually. Common signs include:
Early signs: Unusual tiredness or fatigue, reduced exercise tolerance, difficulty concentrating, feeling cold more easily, and pale skin (especially inside the lower eyelids).
More advanced signs: Shortness of breath during normal activities, heart palpitations, headaches, dizziness, brittle nails, restless legs, and unusual cravings for ice, dirt, or starch (called pica).
In children: Irritability, poor appetite, frequent infections, slow growth, and behavioural or learning difficulties.
If you experience these symptoms, see your GP. A simple blood test (full blood count and iron studies) can confirm whether you are iron deficient.
People who may wish to discuss iron with a GP include those who:
Are experiencing symptoms of iron deficiency (fatigue, shortness of breath, pallor). Are pregnant or planning to become pregnant. Have heavy menstrual periods. Follow a vegetarian or vegan diet. Have a condition that affects iron absorption (coeliac disease, inflammatory bowel disease). Have recently donated blood frequently. Are an endurance athlete.
Your GP can order blood tests to check your iron levels and determine whether you need dietary changes, supplements, or further investigation. Do not self-prescribe high-dose iron supplements without medical advice — excess iron can be harmful.
Yes — about 1.8 times as much. The Australian NRV guidelines set it that way because plant-based iron is harder for your body to grab onto than iron from animal sources.
It's not that plants don't have iron — it's that your gut absorbs it differently. There are two forms of dietary iron: haem iron (found only in animal products) is absorbed much more efficiently (15–35% absorption rate) than non-haem iron (found in plant foods), which is absorbed at only 2–20%. That's why vegetarians and vegans hit iron deficiency more often.
This doesn't mean vegetarians are destined to be iron deficient — it just means being a bit more intentional. Pair iron-rich plant foods with vitamin C, skip the tea or coffee with meals, and lean on iron-fortified foods where you can. Timing matters.
The values used in this calculator are based on the Australian Nutrient Reference Values (NRVs), which are the official dietary guidelines set by the Australian Government's National Health and Medical Research Council (NHMRC).
The NRVs provide Recommended Dietary Intakes (RDIs), Adequate Intakes (AIs), and Upper Levels (ULs) for all essential nutrients. The RDI is the average daily dietary intake level sufficient to meet the nutrient requirements of nearly all (97–98%) healthy individuals in a particular life stage and gender group.
For more information, visit the official NRV website: nrv.gov.au/nutrients/iron
Note: These values may differ from US, UK, or other international guidelines.