Iron deficiency and ADHD

Iron is well known for the transportation of oxygen throughout the body as previously discussed, however, the link between iron deficiency and ADHD is not as well understood.

Attention-deficit/hyperactivity disorder (ADHD) is a condition affecting 12% of school-aged children and a growing number of adults. Impulsive behaviour, hyperactivity and/or inattention are common issues with ADHD. The prevalence of ADHD in student and elite athletes is suggested to be as high as 8% in certain sports. Athletes with ADHD may naturally excel in sports that require quick movements and reactive decision-making such as basketball, netball and baseball due to these athletes’ inherent impulsivity. Physical activity through playing sports also improves the symptoms of ADHD such as inattention, depressive mood, anxiety and impaired cognition.

In most cases, psychosocial interventions are used to manage ADHD. Medications (methylphenidate and amphetamine compounds) may also be used to activate dopamine and noradrenergic neurotransmitter pathways in the brain. This activation may lead to improved attention and concentration but also often come with side effects including increased heart rate and blood pressure, abdominal pain, headache, anorexia, sleep impairment, weight loss, jitteriness and constipation. If not addressed these side effects can impair performance and/or threaten athlete safety.

As both iron and zinc deficiencies impact neurologic functions (poor memory, inattentiveness, and impulsiveness), finicky appetite, and mood changes (sadness and irritability), nutritional adequacy is especially important in ADHD patients. Altered levels of iron and zinc increase the susceptibility, aggravation and progression of ADHD. In children, the severity of iron deficiency has been linked to a 30% increase in inattentive, impulsive, and hyperactive behaviours.

Evidence suggests patients with ADHD may experience lower stores of iron (ferritin) in the liver. This is proposed to be due to higher levels of hepcidin in ADHD patients.  In our previous blog, we explain how Hepcidin is a peptide hormone that acts as the master regulator in iron metabolism and storage in the liver. Hepcidin also tightly influences red blood cell production.

Ferritin levels below 30ng/mL are related to sleep disturbances and a higher incidence of restless leg syndrome which may further compound behavioural issues in ADHD patients. Another mineral which shares the same carrier protein as iron is zinc. Zinc deficiency is also linked to inflammatory prostaglandins, essential enzymes and changes in melatonin and dopamine.

Whilst a food-first approach is preferred, individuals with high nutrient demands may benefit from targeted supplementation.  Iron-rich foods such as kangaroo, red meats, chicken, salmon and zinc-rich foods have been extensively discussed in relation to immunity, anaemia and plant-based athletes.

Supplementation has been shown to be effective in individuals with iron deficiency, especially in the inattentive subtype of ADHD. Iron supplementation has also been shown to decrease the risk of cardiovascular events during treatment with ADHD drugs. A combination of iron and zinc supplements has been shown to be superior to iron alone in alleviating ADHD symptoms, as well as improvement in performance in IQ tests.

Hundreds of athletes have used our handy anaemia tool to help determine the likely risk of having low iron or anaemia. This short quiz is handy if you have experienced iron deficiency in the past and are unsure if your iron stores may be declining.

Want to know more? Contact the Athlete Sanctuary and learn how we can help you.

About the Author: Kate Smyth is a Sports naturopath, nutritionist and female-centric running coach. She is the founder of the Athlete Sanctuary- a holistic healthcare clinic for athletes of all levels and sporting codes. Kate has a thirst for knowledge with two bachelor’s and a master’s degree under her belt. She has been involved in sports for many decades and competed for Australia in the Commonwealth Games and Olympic Games marathons with a personal best time of 2 hours 28 minutes. 

References

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