Iron Deficiency in Active Children - Signs, Symptoms and What Parents Need to Know.

As a sports and nutritional therapist, I spend a lot of time helping people understand how nutrition impacts energy, performance and recovery. But as a mum to an active child, I also see things through a parent’s eyes.

One nutrient that deserves far more attention than it often gets is iron.

Iron deficiency remains one of the most common nutritional deficiencies in children, particularly in toddlers, adolescents and young athletes. Yet the signs can easily be overlooked or dismissed as simply being tired, growing quickly, or going through a busy period.

The reality is that iron plays a vital role in a child’s health, development and physical performance. For active children especially, maintaining healthy iron levels can make a significant difference to how they feel, function and recover.

Why Is Iron So Important?

Iron is essential for the production of haemoglobin, the protein in red blood cells responsible for carrying oxygen around the body. Without enough iron, the body struggles to transport oxygen efficiently, which can affect:

• Energy levels

• Physical performance

• Concentration and learning

• Growth and development

• Immune function

• Recovery from exercise

  
  

For children, adequate iron intake is particularly important because they are growing rapidly and developing both physically and cognitively.

Lets take a look at how much children need..

According to UK dietary recommendations, children require:

Age	Recommended Iron Intake
1–3 years	6.9mg per day
4–6 years	6.1mg per day
7–10 years	8.7mg per day
Boys 11–18 years	11.3mg per day
Girls 11–18 years	14.8mg per day

The higher requirement in teenage girls reflects the additional iron lost through menstruation.

So here is why active children may be at greater risk...

Many active children and young athletes have increased nutritional demands. They are not only supporting growth and development but are also fuelling regular training, sport and physical activity. While most parents focus on protein, carbohydrates and hydration, some of the essential nutrients like iron can often be forgotten.

Research has shown that exercise can increase iron losses through several mechanisms, including:

Sweat Losses

Although the amount lost through sweat is relatively small, it can become significant over time in children who train regularly or participate in endurance-based sports.

Increased Iron Turnover

Exercise places greater demands on the body’s oxygen transport systems, increasing the need for iron to support adaptation and recovery.

Gastrointestinal Losses

Intense exercise can sometimes contribute to small amounts of blood loss from the digestive tract, particularly during prolonged endurance activity.

Foot Strike Haemolysis

This is perhaps one of the lesser-known causes.

Repeated impact during activities such as running can damage a small number of red blood cells within the tiny blood vessels of the feet. This process, known as foot strike haemolysis, has been documented in runners and endurance athletes.

While the amount of iron lost specifically through this mechanism is usually relatively small, it contributes to the overall picture and can become relevant in children who already have low iron stores.

However, in my clinical experience, the biggest issue is often not excessive iron loss but insufficient iron intake to meet increased demands.

Here are some of the common signs of low iron in children...

Iron deficiency doesn’t always present as obvious anaemia straight away.

Some of the early signs can include:

• Persistent tiredness

• Poor concentration

• Irritability

• Pale skin

• Frequent headaches

• Reduced stamina

• Breathlessness during activity

• Poor recovery after exercise

• Increased susceptibility to illness

• Restless sleep

  
  

In sporty children, parents may notice:

• A sudden drop in performance

• Complaints of heavy legs

• Reduced motivation to exercise

• Difficulty keeping up with teammates

• Longer recovery times after training

These symptoms are often attributed to growth spurts, busy schedules or lack of fitness when low iron could actually be playing a role.

The Challenges of Modern Diets

Many children today consume diets that are high in convenience foods but relatively low in iron-rich whole foods.

Some factors that can increase the risk of iron deficiency include:

• Selective or picky eating

• Vegetarian or vegan diets without careful planning

• High intakes of cow’s milk in younger children

• Skipping meals

• Restrictive eating habits

• Increased training loads

  
  

As parents, it’s easy to assume our children are eating enough because they appear healthy and active. However, meeting iron requirements consistently can be more challenging than many people realise.

Best Food Sources of Iron

Animal Sources (More Easily Absorbed)

• Lean red meat (no more than 1x a week)

• Dark poultry meat

• Eggs

  
  

Plant Sources

• Lentils

• Chickpeas

• Beans

• Tofu

• Fortified breakfast cereals (occasionally)

• Spinach and leafy greens

• Pumpkin seeds

  
  

Pairing iron-rich foods with a source of vitamin C can significantly improve absorption.

Good examples include:

• Berries with fortified cereal

• Peppers in a bean-based meal

• Citrus fruits alongside meals

• Kiwi fruit as a snack

  
  

If your child is experiencing ongoing fatigue, poor recovery, reduced exercise tolerance or any of the symptoms mentioned above, it may be worth discussing iron status with a healthcare professional.

Blood testing can help identify whether iron deficiency is contributing to symptoms and guide appropriate treatment if needed but GP's don't love this option as it isn't particulary nice for the child. My advice would be to first take a look at a food first approach. Monitor what foods are being consumed over a week and look to increase Iron based foods where possible.

It’s important not to start iron supplements without professional advice, as excessive iron intake in supplement form can also cause problems.

To wrap things up..

As both a sports and nutritional therapist and a mum, I believe we need to pay more attention to iron in active children.

When a child seems constantly tired, struggles to recover from sport, or suddenly isn’t performing as they once did, it’s easy to assume they need more sleep, more motivation or more training. Sometimes that’s true, but maybe there is more to the story.

Ensuring children receive enough iron-rich foods throughout childhood can support healthy growth, better energy levels, improved recovery and overall wellbeing, helping them thrive both on and off the sports field.

A note to say that this article is intended for educational purposes ( not individualised advice) and based on UK guidelines from the NHS, Dietary recommendations and sports nutrition research available at the time of me writing. Individual medical concerns should always be discussed with a GP or qualified health care professional. Please feel free to contact me for a 1-1 session if further guidance is needed/wanted.

I have listed my references below.

Lucy B x

References

British Dietetic Association (BDA). (2024). Iron Food Fact Sheet. Available at: https://www.bda.uk.com/resource/iron.html

National Health Service (NHS). (2024). Iron Deficiency Anaemia. Available at: https://www.nhs.uk/conditions/iron-deficiency-anaemia/

National Health Service (NHS). (2024). Vitamins and Minerals for Children. Available at: https://www.nhs.uk/start-for-life/baby/weaning/what-to-feed-your-baby/vitamins-for-children/

Scientific Advisory Committee on Nutrition (SACN). (2010). Iron and Health Report. London: The Stationery Office. Available at: https://www.gov.uk/government/publications/sacn-iron-and-health-report

Department of Health. (1991). Dietary Reference Values for Food Energy and Nutrients for the United Kingdom. Report on Health and Social Subjects 41. London: HMSO.

World Health Organization (WHO). (2023). Anaemia. Available at: https://www.who.int/health-topics/anaemia

World Health Organization (WHO). (2020). WHO Guideline on Use of Ferritin Concentrations to Assess Iron Status in Individuals and Populations. Geneva: World Health Organization.

McCormick, R., Moretti, D., McKay, A.K.A., et al. (2020). Iron Deficiency in Athletes: Prevalence and Impact on Performance. European Journal of Applied Physiology, 120(8), 1703–1715.

Peeling, P., Sim, M., Badenhorst, C.E., et al. (2018). Iron Status and the Acute Post-Exercise Hepcidin Response in Athletes. PLoS One, 13(3), e0195224.

Telford, R.D., Sly, G.J., Hahn, A.G., et al. (2003). Footstrike is the Major Cause of Haemolysis During Running. Journal of Applied Physiology, 94(1), 38–42.

Burden, R.J., Pollock, N., Whyte, G.P., Richards, T., Moore, B., Busbridge, M. & Pedlar, C.R. (2015). Effect of Intravenous Iron on Aerobic Capacity and Iron Metabolism in Elite Athletes. Medicine & Science in Sports & Exercise, 47(7), 1399–1407.

British Journal of Sports Medicine (BJSM). (2024). Consensus Statements and Reviews on Iron Deficiency in Athletes. Available via: https://bjsm.bmj.com