Iron deficiency in infants is the most closely monitored nutritional disorder during the first year. Measured intakes in France are frequently below the reference values, but confirmed deficiency remains rare. Here is exactly what the data from ANSES and the World Health Organization show, with the figures to support it.
How much iron does a baby need each day?
ANSES has established precise reference values for this age group. They appear in its opinion on the PNNS dietary guidelines for children aged 0 to 3 years, referral no. 2017-SA-0145, published on June 12, 2019.
Before 6 months, the adequate intake is 0.3 mg per day. The infant relies on the reserves built up during pregnancy, while breast milk or formula provides the rest.
Between 6 and 11 months, the average nutritional requirement rises to 8 mg per day. This is the highest value throughout early childhood, and the difference from the preceding period is considerable.
Between 12 and 35 months, this requirement falls back to 5 mg per day. The peak therefore occurs precisely when the reserves present at birth are depleted and complementary feeding begins.
Why the requirement rises sharply around 6 months
The iron reserves built up during the last trimester of pregnancy are depleted around 6 months of age in a full-term baby. From then on, iron must come from the diet.
At the same time, blood volume increases rapidly with growth. The daily requirement relative to body weight is then among the highest throughout life.
What the French data show
The same ANSES opinion quantifies the proportion of children whose iron intake is below the average nutritional requirement. The results are high.
Among 6- to 11-month-olds, 51.1% of children have an intake that is insufficient in relation to this reference. Among 12- to 35-month-olds, the proportion is 30.9%.
These figures describe intakes, not diseases. The same document notes that the available clinical data place true iron deficiency at around 3% among children aged 0.8 to 2 years.
The gap between these two sets of figures is important to understand. An intake below the average requirement of a population does not automatically cause an individual deficiency, because the body adjusts its absorption.
What can and cannot be concluded
We can conclude that iron is the nutrient under the greatest strain in this age group in France. This is a solid finding, repeated from one survey to the next.
We cannot conclude that one child in two is iron deficient. This interpretation, common in the press, confuses two distinct indicators.
Anemia worldwide: WHO figures
Worldwide, the World Health Organization estimates that 40% of children aged 6 to 59 months are affected by anemia, representing 269 million children. These data concern 2019 and are cited in the fact sheet updated on February 10, 2025.
WHO identifies three major causes: nutritional iron deficiency, inherited red blood cell disorders such as thalassemia and sickle cell disease, and malaria.
The situation in France is not comparable to this global average, which is heavily influenced by areas where malaria is endemic and by undernutrition. It does, however, convey the scale of the issue.
What are the consequences for a child's development?
This is what makes attention to this nutrient important. According to WHO, severe anemia causes cognitive and motor impairments in children.
The organization also describes developmental delays and behavioral problems, along with reduced motor activity, social interactions, and attention.
These effects concern cases of established anemia, not simply somewhat borderline intakes. Nevertheless, they explain why medical monitoring during the first year includes vigilance on this issue.
The link with motor development is consistent with WHO recommendations on physical activity for young children, and with the motor milestones detailed in our article on fine and gross motor skills.
Where does iron in a baby's diet come from?
ANSES identifies the main contributors to iron intake among young children in France. These are follow-on formulas and so-called growing-up milks.
Vegetables and legumes come next. Meat, fish, and eggs provide iron that is better absorbed, but often in modest quantities at this age.
One practical point matters as much as the source itself: iron from plant foods is absorbed much more effectively in the presence of vitamin C. Serving a vegetable and fresh fruit at the same meal has a real effect.
The timing and principles of this introduction are detailed in our article on what ANSES says about complementary feeding.
The role of the milk consumed
The type of milk consumed after 6 months has a major impact on iron intake. This is why follow-on formulas rank among the leading contributors identified by ANSES.
The choice between follow-on formula, growing-up milk, and cow's milk is an individual medical decision. The doctor caring for the child is the person to consult about it.
Iron deficiency in infants: which children are most at risk?
Certain situations reduce iron reserves at birth or increase requirements. They are well identified.
Children born prematurely are the first group concerned, because reserves are built up mainly during the last trimester. Our article on prematurity figures in France explains the size of this population.
Children with a low birth weight, twins, and children whose diet is very poorly diversified after 8 months are also among those requiring monitoring.
WHO also mentions a simple obstetric measure: delaying clamping of the umbilical cord for at least one minute after birth improves the newborn's iron reserves.
Should you give your child an iron supplement?
No, not on your own initiative. Iron supplementation requires a prescription, because excess iron is toxic and accidental poisonings in young children have been documented.
Signs suggestive of deficiency are nonspecific: paleness, unusual fatigue, irritability, and reduced appetite. They warrant a medical consultation, not a trip to the pharmacy.
Diagnosis is based on a blood test interpreted by a doctor. No isolated symptom is enough to draw a conclusion.
Key takeaways
Iron intakes among infants in France are frequently below ANSES reference values, with 51.1% of 6- to 11-month-olds affected, but confirmed deficiency remains around 3%.
The requirement peaks between 6 and 11 months, at 8 mg per day. This is the period when the contents of the plate and the type of milk matter most.
The sensible approach has two parts: introduce a genuinely varied diet from 6 months onward, and let the doctor decide on any supplementation. Our frequently asked questions answer questions about our products and their certifications.
Sources: ANSES, opinion on updating the PNNS dietary guidelines for children aged 0 to 3 years, referral no. 2017-SA-0145, June 12, 2019. World Health Organization, “Anemia” fact sheet, updated February 10, 2025.
