Obesity in children and adolescents
Professor Elisabeth Fernell gives an overview of childhood and adolescent obesity and its link to neurodevelopmental conditions, such as ADHD.
The term obesity is defined based on a measure of BMI (Body Mass Index), BMI = weight in kilograms / (height × height in meters). For children and adolescents, a specially adapted version of BMI is used: Iso-BMI, where obesity is defined as a value of ≥ 30. Overweight is defined as an Iso-BMI between 25–30.
In the Swedish National Care Program for the Treatment of Obesity in Children and Adolescents (2023) (1), the importance of early diagnosis is emphasised, as well as the need for clear collaboration throughout the entire chain of care: child health services, school health medical services, primary care, and specialised care. The care program highlights that combined lifestyle intervention (CLI), including support for behavioural changes related to dietary habits and physical activity, is the foundation of all obesity treatment and aims to promote healthy weight development.
In addition to specific medical aspects of obesity addressed in the care program (risk of high blood pressure, risk of elevated blood lipids, liver involvement, orthopedic problems, and impaired dental health), it is also emphasised that various conditions can contribute to obesity in children, adolescents, and adults.
Several neurodevelopmental/neuropsychiatric disabilities can also affect eating behaviour. The cognitive/executive difficulties associated with ADHD involve problems such as self-regulation, impulse control, planning, directing behaviour in a goal-oriented manner, and inhibiting behaviour. ADHD is the most common neurodevelopmental disorder in children. The prevalence is approximately 5–8% worldwide (2). The symptom profile varies greatly, both between individuals and across the lifespan. ADHD exists in different forms, including one characterised by pronounced hyperactivity and impulsivity, as well as a form dominated by significant difficulties with attention/concentration, Attention-Deficit Disorder (ADD), in which hyperactivity/restlessness and deficits in impulse control are not present.
Author
Elisabeth Fernell
Neurodevelopmental conditions / ESSENCE
Conditions associated with obesity may occur either alone or in various combinations. ADHD is therefore the most common, but intellectual disability and autism are also disabilities that may occur in children with obesity. It is not uncommon for children with autism, as well as those with intellectual disability, to also have difficulties consistent with ADHD. The concept of ESSENCE (Early Symptomatic Syndromes Eliciting Neurodevelopmental Clinical Examinations) highlights the fact that disabilities often occur in combinations (3).
It is therefore important for teams that assess and provide interventions for children with obesity and their parents to be attentive to signs of ADHD as well as other neurodevelopmental disabilities (4, 5).
A large study by Cortese and colleagues (6) demonstrated a strong association between obesity and ADHD, showing an increased risk of higher food intake with subsequent weight gain. The prevalence of obesity in adults increased by 70% when comorbid ADHD was present, and by 40% in children with ADHD, compared with individuals without ADHD.
A substantial body of research-based evidence shows that ADHD symptoms can contribute to overeating, particularly of easily accessible food temptations (fast food). Foods high in fat and sugar can, like certain drugs, lead to addictive behaviours, and overeating in ADHD may represent a form of self-medication (7).
In an American study, the impact of ADHD on BMI and blood pressure over time was examined, with and without pharmacological treatment for ADHD. The study group consisted of children and adolescents aged 6–19 years who attended a paediatric clinic for overweight/obesity. The results showed that adolescents with ADHD who were treated with ADHD medication had a significantly faster reduction in BMI compared with adolescents with ADHD who did not receive such pharmacological treatment. Underlying factors contributing to weight gain/obesity included overeating, binge eating, and consumption of more unhealthy, high-calorie foods. The study also concluded that the results suggest that adolescents with obesity and ADHD who are not treated with ADHD medication may not benefit from standard weight-management advice to the same extent as adolescents without ADHD and those with ADHD who are treated with medication (8).
ADHD therefore needs to be recognised in order to provide appropriate support and interventions for children and adolescents, as well as adults, with obesity (9–11). Many individuals improve with pharmacological treatment. A Swedish study showed weight normalisation in half of the children with ADHD and obesity who were treated with ADHD medication (5). Since ADHD medications may cause reduced appetite as a side effect, it is important to emphasise that the goal of pharmacological treatment for ADHD is to improve executive functioning, leading to better appetite regulation and reduced impulsive eating. This therefore needs to be carefully monitored during medical follow-up.
In paediatric teams that assess and provide treatment interventions for children and adolescents with obesity, it is of very great importance to identify and evaluate whether there is an underlying neuropsychiatric/cognitive condition, including ADHD.
Families may also need support through School Health Services or Child Health Services in requesting a neurodevelopmental/neuropsychiatric assessment within the healthcare system.
Recently published articles on obesity and children and adolescents
Lundh H, Arvidsson D, Greven C, Fridolfsson J, Börjesson M, Boman C, Lauruschkus K, Lundqvist S, Melin K, Bernhardsson S. Physical activity and sedentary behaviour amongst children with obesity - exploring cross-sectional associations between child and parent. J Act Sedentary Sleep Behav. 2025 Feb 13;4(1):2. doi: 10.1186/s44167-025-00072-0. PMID: 40217557; PMCID: PMC11960359.
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Garcia-Argibay M, Lundström S, Cortese S, Larsson H. Trends in Body Mass Index Among Individuals With Neurodevelopmental Disorders. JAMA Netw Open. 2024 Sep 3;7(9):e2431543. doi: 10.1001/jamanetworkopen.2024.31543. PMID: 39230900; PMCID: PMC11375475.
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Landgren V, Svensson L, Törnhage CJ, Theodosious M, Gillberg C, Johnson M, Knez R, Landgren M. Neurodevelopmental problems, general health and academic achievements in a school-based cohort of 11-year-old Swedish children. Acta Paediatr. 2024 Mar;113(3):506-516. doi: 10.1111/apa.16989. Epub 2023 Oct 12. PMID: 37823347.
References
1. Nationellt vårdprogram för behandling av obesitas hos barn och ungdomar. Nationellt programområde för barns och ungdomars hälsa. Sveriges regioner i samverkan,
2. Ayano G, Demelash S, Gizachew Y, Tsegay L, Alati R.The global prevalence of attention deficit hyperactivity disorder in children and adolescents: An umbrella review of meta-analyses. J Affect Disord. 2023;339:860-866.
3. Gillberg C. ESSENCE samlar diagnoserna till en helhet. Läkartidningen. 2014;111:CU47
4. Hölcke M, Marcus C, Gillberg C, Fernell E. Paediatric obesity: a neurodevelopmental perspective. Acta Paediatr 2008;97(6):819-21.
5. Fast K, Björk A, Strandberg M, et al. Half of the children with overweight or obesity and attention-deficit/hyperactivity disorder reach normal weight with stimulants. Acta Paediatr. Epub 20 apr 2021. doi: 10.1111/apa.15881.
6. Cortese S, Moreira-Maia CR, St Fleur D, Morcillo-Peñalver C, Rohde LA, Faraone SV. Association Between ADHD and Obesity: A Systematic Review and Meta-Analysis. Am J Psychiatry. 2016;173(1):34-43.
7. El Archi S, Cortese S, Ballon N, et al. Negative Affectivity and Emotion Dysregulation as Mediators between ADHD and Disordered Eating: A Systematic Review. Nutrients. 2020;12(11):3292.
8. Kollin SR, Lim CS, Lee AA. The longitudinal influence of ADHD status and stimulant medication on body mass index and blood pressure among youth with obesity. Pediatr Obes. 2023;18(9):e13058.
9. Wentz E, Björk A, Dahlgren J. Neurodevelopmental disorders are highly over-represented in children with obesity: A cross-sectional study. Obesity (Silver Spring). 2017;25(1):178-184.
10. Landgren M. Obesity, yet another symptom of a neurodevelopmental disorder. Acta Paediatr. 2021;110(10):2668-2670.
11. Fernell E, Wentz E, Gillberg C. The importance of screening for ADHD in children and adolescents with obesity. Acta Paediatr. 2013;102(10):e436-7.