By Tali Engor, B.Sc. Pharm, B.Sc. Pharmaceutical Chemistry, licensed pharmacist and pharmaceutical chemist, founder of C.A.T. Center
Some children will eat only a particular type of pasta, bread with the crusts removed, or one familiar yoghurt. For many families of children with autism, expanding the menu is part of everyday life: introducing a new flavour, adjusting a texture, and sometimes celebrating even a willingness to touch an unfamiliar food.
Behind these daily efforts lies an important question: Are the foods a child eats providing the nutrients needed for growth and everyday functioning?
Iron is one nutrient worth considering. It contributes to oxygen transport, energy production and nervous system function. As iron stores become depleted, children may experience fatigue, reduced stamina and difficulty concentrating, sometimes before anaemia develops.
For a child with a restricted diet, these changes offer a reason to consider nutrition and physical health alongside developmental and behavioural factors.
Selective eating: What is actually on the menu?
Not all restricted diets are alike.
A child who eats only a few foods but regularly consumes iron-fortified products may have a very different iron intake from a child who avoids meat, legumes and fortified foods altogether. The number of accepted foods is therefore only part of the picture. What those foods are, and how much the child eats, also matters.
In a study published in The Journal of Pediatrics, involving 111 children with and without autism, researchers found greater food refusal and a more limited food repertoire among children with autism. A narrower food repertoire was associated with inadequate intake of a greater number of nutrients. [1]
This finding highlights the value of an individual assessment. A practical starting point is to record several typical days of eating, including foods, approximate portions, drinks and supplements.
Why iron matters beyond haemoglobin
Most parents are familiar with the connection between iron and anaemia. Iron also has other important roles: it contributes to enzyme activity, energy production, and the development and functioning of the nervous system. [2]
Iron deficiency may be associated with fatigue, reduced stamina and difficulty concentrating. Children do not always describe these changes in words. Parents may notice that their child tires more quickly, participates less in a favourite activity, or struggles to stay with a task that previously seemed easier.
Knowing the child’s usual patterns is valuable here. What has changed? When did it begin? Did it coincide with a further narrowing of the diet, an illness or disrupted sleep?
These observations help guide assessment, as the same signs can have several possible causes.
Normal haemoglobin does not tell the whole story
Iron stores can become depleted before haemoglobin levels fall. A child can therefore have normal haemoglobin and still have low iron stores.
One of the main tests used to assess these stores measures ferritin, a protein that stores iron in the body. Haemoglobin and ferritin provide different information: the former helps assess anaemia, while the latter helps assess iron reserves. [3,7]
The timing of testing matters, too. Ferritin can rise during infection or inflammation, so an apparently normal result needs to be interpreted in the context of the child’s health. Where appropriate, a doctor may also consider a complete blood count and inflammatory markers such as C-reactive protein (CRP).
A serum iron test alone does not provide a reliable picture of iron stores. Understanding the result requires bringing together the child’s diet, medical history and laboratory findings.
When a child eats things that are not food
Repeatedly eating soil, paper or other non-food substances in a way that is inappropriate for a child’s developmental stage is known as pica.
In a study published in Pediatrics, pica was reported more frequently among young children with autism than among children in the general-population control group. [5]
Pica can be associated with sensory and developmental factors and, in some cases, nutritional deficiencies. When it occurs, an assessment should therefore include consideration of the child’s iron status. [6]
Clinical insight
Clinical Perspective by Tali Engor, B.Sc. Pharm, B.Sc. Pharmaceutical Chemistry
A useful nutritional assessment brings together details that are sometimes considered separately: the foods a child eats, the changes parents notice and the laboratory results.
For example, a diet containing very few sources of iron, together with new fatigue and low ferritin, creates a picture that warrants focused attention. The same complaint of fatigue in a child recovering from an illness calls for consideration of recovery itself and the effects of inflammation on test results.
The goal is to identify a need that can be addressed, understand how it developed and monitor the response over time. For children with selective eating, the approach also needs to fit what the family can realistically implement, including accepted textures, mealtime routines and possible difficulties taking supplements.
Iron and sleep: What have studies found?
The possible relationship between iron status and sleep has attracted interest from parents and researchers.
In a randomised controlled trial involving 20 children with autism, sleep difficulties and low-normal ferritin levels, iron supplementation improved iron status. Researchers also found an improvement in a secondary clinical rating of sleep. However, there was no statistically significant improvement in the primary objective measures of time taken to fall asleep or time spent awake after initially falling asleep. [8]
This small study illustrates the importance of defining and tracking the intended outcome. Replenishing iron stores is a measurable goal; its effect on sleep may vary from child to child.
When sleep difficulties persist, iron status may be considered as part of an assessment, depending on the circumstances, alongside sleep habits and other medical factors.
Improving iron intake without turning meals into a battle
Progress starts with what is already manageable.
Sources of iron include meat, fish, lentils, beans, tofu and iron-fortified cereals. Vitamin C helps the body absorb iron from plant foods, so pairing an iron-containing food with a fruit or vegetable the child already accepts can be useful. [2]
For a child with texture sensitivities, a small adjustment may be more practical than replacing an entire meal. The aim is to gradually expand the available options while maintaining adequate intake and keeping familiar, accepted foods on the menu.
If iron deficiency is identified, dietary changes recommended by a dietitian may be only part of the response. An iron supplement may also be needed under professional guidance, with an appropriate dose and follow-up to assess the response and replenishment of iron stores. [3]
FAQs
- Does every child with autism need iron testing? The decision depends on age, diet, symptoms and medical history. A very restricted diet, pica or unexplained fatigue can be reasons to discuss an assessment of iron status with the child’s paediatrician.
- Can a child have iron deficiency without anaemia? Yes. The body can draw on its iron stores before haemoglobin levels fall. Normal haemoglobin therefore does not rule out depleted iron stores.
- Does normal ferritin rule out iron deficiency? Not always. Ferritin can rise during infection or inflammation. A doctor interprets the result alongside the clinical picture and additional tests where needed.
- Can correcting iron deficiency improve concentration? Iron deficiency may contribute to difficulty concentrating, so correcting it may help when it is one of the contributing factors. The extent of any improvement depends on the child’s circumstances and other factors affecting attention.
- Is selective eating a reason to start an iron supplement? Selective eating alone is not enough to determine whether a supplement is needed. Both the decision and the dose should be tailored to the child. Different products contain different amounts of elemental iron, and excessive iron intake can be dangerous.
Takeaway
- Selective eating warrants attention to the nutritional composition of the diet, not just the number of foods a child accepts.
- Iron contributes to oxygen transport, energy production and nervous system function.
- Iron stores can become depleted even when haemoglobin remains normal.
- Ferritin helps assess iron stores, but infection and inflammation must be considered when interpreting it.
- Pica and persistent changes in energy or everyday functioning are reasons to seek an appropriate assessment.
- Addressing an identified deficiency should involve an individual approach, consideration of its cause and follow-up.
Selected references
- Bandini LG, Anderson SE, Curtin C, et al. Food Selectivity in Children with Autism Spectrum Disorders and Typically Developing Children. The Journal of Pediatrics. 2010;157(2):259–264. Read the study
- National Institutes of Health, Office of Dietary Supplements. Iron: Fact Sheet for Health Professionals. Read the fact sheet
- The Royal Children’s Hospital Melbourne. Clinical Practice Guidelines: Iron Deficiency. Read the guidelines
- Iron and Attention in Children. Expert guidance from Engor T, B.Sc. Pharm, B.Sc. Pharmaceutical Chemistry. Read the article
- Fields VL, Soke GN, Reynolds A, et al. Pica, Autism, and Other Disabilities. Pediatrics. 2021;147(2):e20200462. Read the study
- Autism Speaks. The Pica and Autism Connection: Help and Perspective. Expert guidance from Lynn Cole. Read the guidance
- World Health Organization. WHO Guideline on Use of Ferritin Concentrations to Assess Iron Status in Individuals and Populations. 2020. Read the guideline
- Reynolds AM, Connolly HV, Katz T, et al. Randomized, Placebo-Controlled Trial of Ferrous Sulfate to Treat Insomnia in Children With Autism Spectrum Disorders. Pediatric Neurology. 2020;104:30–39. Read the study
About the author
Tali Engor, B.Sc. Pharm, B.Sc. Pharmaceutical Chemistry, is a licensed pharmacist, holds degrees in pharmacy and pharmaceutical chemistry, and is the founder of C.A.T. Center. Her work focuses on using dietary information and laboratory findings to guide individualised nutritional and supplement support for children with autism.
Disclaimer
The information in this article is for general educational purposes. It is not a substitute for professional medical advice, diagnosis, or treatment.
Consult a licensed healthcare professional before starting or changing supplements or dietary regimens. Do not disregard medical advice or delay seeking medical care based on this article. Individual results vary, and no specific outcome is guaranteed.
Keep iron supplements out of the reach of children. In the event of a suspected overdose, contact a poison control centre or seek emergency medical assistance immediately.
