By Aurélie Dubuis, paediatric nutritionist and co-founder of Nuré

Iron is an essential mineral during childhood. It carries oxygen around the body and contributes to children's normal cognitive development. This guide answers the questions parents in Europe most often ask about children aged 3 and over, using French reference values (ANSES):

• How much iron does my child need?
• Which foods really provide it?
• How can I tell if my child is short of iron?
• When does a supplement make sense?

The essentials in 30 seconds

• Needs in France (ANSES): 4 mg/day from 3 to 6 years, 6 mg/day from 7 to 11, 11 mg/day in adolescence (13 mg for teenage girls with heavy periods).
• Iron deficiency is the most common nutritional deficiency in children, especially in young children and teenage girls.
• Iron from meat and fish (haem iron) is better absorbed than iron from plants. Vitamin C improves the absorption of plant iron.
• Only your doctor can confirm a deficiency, usually with a blood test that includes ferritin.
• Food comes first. A supplement can help when intake is insufficient, ideally on the advice of a health professional. It does not replace treatment for anaemia.

What does iron do in children?

Iron is mainly used to make haemoglobin, the protein in red blood cells that carries oxygen throughout the body. It is also part of myoglobin, which stores oxygen in the muscles, and is involved in many reactions needed for growth.

Iron contributes in particular to:

• normal cognitive development of children;
• normal formation of red blood cells and haemoglobin;
• normal energy metabolism;
• normal function of the immune system;
• the reduction of tiredness and fatigue.

During childhood, blood volume and muscle mass increase quickly, so iron is needed to make ever more haemoglobin and myoglobin. The developing brain needs it too. That is why iron needs are high relative to a child's weight, especially during growth spurts such as adolescence.

How much iron does a child need?

In France, ANSES recommends 4 mg of iron a day between 3 and 6 years and 6 mg between 7 and 11. Needs then rise sharply in adolescence, especially for girls who have started their periods.

These values are population reference intakes: they show the daily intake from food that covers the needs of almost all healthy children. They are not the amount in a supplement, and not a treatment dose for a deficiency: these are three different things.

In Belgium and Switzerland, official reference values are somewhat higher, around 7 to 11 mg a day depending on age. The difference comes mainly from different assumptions about how much iron is actually absorbed, not from children having different needs. The advice is the same everywhere: an iron source at every meal, and your doctor's advice if in doubt.

And before age 3?

Babies and children under 3 have specific needs and recommendations, especially regarding infant formula and the introduction of solid foods. This guide focuses on children aged 3 and over. For a younger child, ask the paediatrician.

Is iron deficiency common in children?

Yes: it is the most widespread nutritional deficiency in children and adolescents, according to recommendations from the Swiss paediatric haematology group. It mainly affects three periods: the first months of life, the preschool years and adolescence, particularly in girls.

Figures vary with age, country and the ferritin threshold used. In France, the national health insurance (Assurance Maladie) estimates that 20 to 30% of children lack iron during their first three years. A French study of 561 two-year-olds found a deficiency in 7% of them. It also showed that food alone did not cover the needs of 63% of these children. So insufficient intake does not necessarily mean a deficiency: the body adapts by absorbing more iron when its stores fall. A deficiency can develop later, once stores are used up.

The takeaway: deficiency is common, but it does not affect every child. That is why it helps to know who is most at risk.

Which children are most at risk of iron deficiency?

Children who eat few iron sources, vegetarian children and teenage girls are the most exposed. The main situations to watch:

• A very selective diet. A phase of food refusal is common. It is worth seeking advice when it excludes meat, fish, eggs and legumes over a long period.
• A vegetarian or vegan diet. Plant iron is less well absorbed. A vegan diet in children should be supported by a professional.
• A high intake of milk or dairy products. In excess, they replace iron-rich foods. Calcium can also reduce the absorption of iron eaten at the same meal.
• Adolescence. Needs rise with growth, and periods mean an extra loss of iron for girls. Very sporty teenagers are also more exposed.
• Certain medical situations. Repeated bleeding, or chronic digestive or inflammatory diseases: these always need medical follow-up.

Which foods provide the most iron?

Black pudding, offal, red meat, seafood and legumes are among the best sources of iron. But for a parent, the content per 100 g matters less than the amount actually eaten. A child easily eats 100 g of lentils, but rarely 100 g of pumpkin seeds. So the tables below also show the iron in a realistic portion.

Animal sources

Plant sources

Source: Swiss Food Composition Database (Federal Food Safety and Veterinary Office, FSVO), version 7.1. Portions are practical guides, not individual recommendations.

Haem and non-haem iron: what's the difference?

Haem iron, found in meat, fish and seafood, is better absorbed than the non-haem iron in plants, eggs and dairy. According to ANSES, haem iron makes up 15 to 80% of the iron in animal flesh, depending on the species and the cut.

How well non-haem iron is absorbed depends more on the rest of the meal. As a result, 2 mg of iron in two different foods does not necessarily give the body the same amount of usable iron.

How can you improve iron absorption?

Pairing a plant source of iron with a vitamin C-rich food improves its absorption. A few easy pairings:

• lentils + pepper or tomato;
• chickpeas + lemon juice;
• tofu + broccoli;
• oat flakes + kiwi or strawberries;
• beans + a raw vegetable starter.

On the other hand, tea, phytates (found in whole grains and unsoaked legumes) and large amounts of dairy at the same meal can reduce the absorption of plant iron. There's no need to cut these foods out: simply vary meals and don't concentrate everything in the same one.

What does an iron-rich day look like?

One iron source at each main meal is usually enough. For example: oat flakes at breakfast, meat, fish or legumes at lunch and dinner, and an egg or wholemeal bread as an afternoon snack. Add a fruit or vegetable rich in vitamin C to the plate. On meat-free days, rely on legumes, tofu or eggs at several meals. It's intake over several weeks that counts, not a single day.

Tiredness, paleness… How can I tell if my child is short of iron?

Only your doctor can confirm that your child is short of iron. Possible signs are tiredness, paleness, irritability, reduced appetite, difficulty concentrating and frequent infections. However, these signs are not only linked to a lack of iron. And iron stores can also fall without any visible sign.

The role of the doctor or nutritionist is central at every step:

• Assessing the situation: your child's diet, growth, symptoms and history.
• Prescribing a blood test if needed. In France, measuring ferritin, which reflects iron stores, is the first-line test.
• Interpreting the results, which depend on age and on any infection or inflammation.
• Choosing the right approach: dietary advice, a food supplement to top up intake, or medical treatment if there is anaemia.

When to talk to your doctor: tiredness or paleness lasting several weeks; a diet very low in meat, fish, eggs or legumes; a vegan diet; heavy periods in a teenage girl; frequent illness.

Good to know: a child can be short of iron without being anaemic. Falling iron stores come before anaemia, and this is the most common form of deficiency in children.

Should you give your child an iron supplement?

Not automatically: a supplement makes sense when food doesn't cover needs, ideally on the advice of a health professional.

Two situations need to be told apart:

• Supplementing the diet. A food supplement provides a moderate, defined amount of iron on top of meals, for example for a child who eats few iron sources.
• Treating a diagnosed deficiency or anaemia. This is a medical matter: the doctor prescribes a suitable dose and duration, with a follow-up blood test. A food supplement does not replace this treatment.

How do you choose an iron supplement for a child?

If supplementation is being considered, six criteria help you compare products:

1. The amount of iron. It should be clearly stated and suited to the child's age. In France, the DGCCRF (consumer protection authority) sets 7 mg a day as the maximum recommended iron content in supplements intended for children. More is not better.
2. The form of iron. Bisglycinate, pyrophosphate, liposomal form… Forms differ in how well they are absorbed and tolerated.
3. Digestive tolerance. Some forms of iron can cause stomach aches or constipation. For regular use, this is a key criterion.
4. Taste. Iron often tastes metallic. A supplement the child refuses is useless.
5. The format. Syrup, drops, capsule or chewable tablet: it should suit the child's age and fit easily into the daily routine.
6. The full ingredient list. Look beyond the amount of iron: added sugars, sweeteners, controversial additives, colourings, preservatives.

What is liposomal iron?

In liposomal iron, the iron is wrapped in a thin layer of lipids (a liposome). This technology is being studied to improve digestive tolerance and avoid the metallic taste, because the iron has less direct contact with the mouth and the lining of the gut.

It's a promising approach, but not all liposomal forms are equal, and no form of iron is better in every situation. For a child, what matters is the whole package: a well-tolerated form, a suitable amount, a good taste and taking it regularly.

Kids Iron: Nuré's choice

This reasoning guided us when we created Kids Iron, a chewable tablet designed for children from age 3.

• 7 mg of liposomal iron (Liposovit®) per tablet, the maximum recommended in France for a supplement intended for children.
• Natural peach flavour, with no metallic taste.
• Prebiotic fibre (chicory inulin) and a fruit base, with no sweeteners, preservatives, controversial additives or artificial colourings.
• 1 tablet a day, chewed or crushed into a fruit compote.
• Take it at least 2 hours apart from other supplements, because iron can reduce the absorption of magnesium or zinc.
• Also suitable for teenagers, especially girls who have started their periods.

Kids Iron is a food supplement, not a treatment for anaemia. Before any supplementation, we recommend talking to your health professional, who can prescribe a blood test if needed.

Discover Kids Iron →

Frequently asked questions

Which food contains the most iron?

Black pudding and offal such as liver are among the richest foods in iron. For a child, how often and how much is actually eaten matter more: regular lentils or minced beef provide more iron day to day than a very rich food eaten rarely.

Is spinach really rich in iron?

Less than its reputation suggests. Spinach contains a little less iron than lentils, and it's non-haem iron, which is poorly absorbed. Legumes, red meat and seafood remain better sources.

Which fruit contains the most iron?

Fruits are poor sources of iron. Their value lies elsewhere: vitamin C-rich fruits such as kiwi, citrus or strawberries help the body absorb the plant iron in the meal.

My child hardly eats any meat: are they at risk of iron deficiency?

Not necessarily, but the risk is higher. Legumes, tofu and eggs can top up intake, as long as they are eaten regularly and paired with vitamin C. If the diet stays very limited, talk to your doctor.

My child is tired: should I give them iron?

Not on that sign alone. Tiredness has many possible causes. If it lasts or worries you, see your doctor: a blood test will show whether iron is involved.

Low ferritin in children: what should you do?

Ferritin reflects the body's iron stores. Normal values depend on age, the laboratory and any inflammation. Depending on the result, your doctor will suggest dietary advice, a supplement or treatment, with a follow-up check later on.

Does iron cause constipation in children?

Some forms of iron can cause constipation or stomach aches, especially at high doses. The form of iron and the dose matter: it's a criterion to look at for regular use. If digestive problems appear, talk to your health professional.

What time of day should iron be given?

The simplest is to choose a fixed time, away from milk and other supplements. Regularity matters more than the exact time.

How long should iron be given?

It depends on the situation and on the child's iron status at the start. Rebuilding iron stores generally takes several months. When a professional recommends supplementation, they decide the duration and any follow-up blood test.

Can Kids Iron be taken with other Nuré supplements?

Yes, taking the iron about 2 hours apart from the other supplements. This is also why our Multi Complex contains no iron: iron is best taken on its own.

Is Kids Iron suitable for teenage girls?

Yes. Iron needs rise in adolescence, especially for girls who have started their periods. A blood test is still advisable in case of heavy periods or persistent tiredness.

From what age can Kids Iron be taken?

Kids Iron is intended for children aged 3 and over. For a younger child, ask the paediatrician.

Key takeaways

From age 3, a varied diet with an iron source at every meal covers the needs of most children. Look at the portion actually eaten and the form of iron, not just the amount on the label. Picky eaters, vegetarian children and teenage girls deserve particular attention. And if you suspect a deficiency, ask your doctor to check it rather than supplementing blindly.

Our philosophy at Nuré: food first, and when support is useful, a formula designed for children. That is the thinking behind Kids Iron: 7 mg of liposomal iron per chewable tablet, from age 3.

Discover Kids Iron →

About the author

Aurélie Dubuis, paediatric nutritionist and co-founder of Nuré.

The information in this guide is educational and does not replace an individual diagnosis or medical advice.

Sources

• ANSES: dietary reference values for vitamins and minerals
• Swiss Food Composition Database (FSVO), version 7.1
• DGCCRF: health recommendations on nutrients in food supplements (2019)
• Mattiello V. et al., recommendations of the SPOG Pediatric Hematology Working Group, European Journal of Pediatrics, 2020
• Le Quotidien du Médecin: ferritin as the first-line test (HAS)
• Université Paris Cité / Inserm: study of 561 two-year-olds
• Pourquoi Docteur, citing the Assurance Maladie
• Belgian Superior Health Council, advice no. 9285 (2016)
• Swiss nutritional reference values (FSVO, 2022), via the Swiss Society for Nutrition