Beyond inattention: eating attitudes, metabolic parameters and their clinical correlates in adults with ADHD — a case control study

Aim

Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental condition characterized by persistent inattention, hyperactivity, and impulsivity causing significant functional and social impairment across the lifespan (1). Global prevalence of adult ADHD is estimated between 2.5% and 4.9% (2). Beyond its core symptoms, ADHD is increasingly recognized for its association with maladaptive eating behaviors and adverse metabolic outcomes. This relationship is driven by dopaminergic reward processing deficits, shared genetic pathways linking impulsivity to disordered eating, and emotion dysregulation — a frequent feature of adult ADHD that may function as a catalyst for food-related impulsivity (3,4). This study examined the relationship between nutritional knowledge, eating attitudes, and metabolic profiles in adults with ADHD, with a specific focus on the mediating roles of hyperfocusing and emotion dysregulation.

Materials and Methods

This case-control study included 58 adults with DSM-5-diagnosed ADHD and 60 age- and sex-matched healthy controls. Exclusion criteria comprised intellectual disability (IQ < 80), psychotic disorders, and established clinical eating disorder diagnoses, in order to isolate subclinical eating attitudes and behaviors. Assessments included the ASRS v1.1, Hyperfocusing Scale (HS), Emotion Regulation Questionnaire (ERQ), Sleep Hygiene Index (SHI), State-Trait Anxiety Inventory (STAI TX-1/TX-2), and Beck Depression Inventory (BDI). Eating behaviors were evaluated with the TFEQ-R21 and the Attitude Scale for Healthy Nutrition (ASHN), which distinguishes theoretical nutritional knowledge from actual behavioral attitudes toward food. BMI, waist circumference, and waist-to-height ratio were recorded by trained clinicians. Statistical analyses included independent t-tests, Mann-Whitney U tests, and ANCOVA controlling for age and psychological comorbidities.

Results

The ADHD group demonstrated significantly higher metabolic risk markers, including BMI (M=24.61 vs M=23.58 kg/m², Z=2.61, p=0.009), waist circumference (M=80 vs M=88, Z=2.87, p=0.004), and waist-to-height ratio (M=0.47 vs M=0.52, Z=3.13, p=0.002) relative to controls. While nutritional knowledge was comparable (t=0.08, p=0.94), overall healthy eating attitudes (ASHN) were markedly lower in the ADHD group (t=3.45, p=0.001). Specifically, participants with ADHD exhibited significantly greater uncontrolled eating (t=3.39, p=0.001) and emotional eating (t=2.95, p=0.004) while cognitive restriction levels were similar in both groups. Depression, anxiety (state and trait), emotional dysregulation, and hyperfocusing levels were also higher in the ADHD group (respectively: t=3.95, p<0.001; t=3.40, p=0.001; t=4.68, p<0.001; t=4.37, p<0.001; t=9.03, p<0.001). The ADHD group had worse sleep hygiene (t=4.39, p<0.001). ASHN scores were inversely correlated with depression, state and trait anxiety, emotion dysregulation, and sleep hygiene in the ADHD group. ANCOVA confirmed that ADHD diagnosis remained a pivotal predictor of the waist-to-height ratio, with uncontrolled eating and emotion dysregulation serving as significant covariates.

Conclusion

Adults with ADHD are predisposed to adverse metabolic outcomes mediated by maladaptive eating patterns, which appear fundamentally linked to emotion dysregulation and impulsive reward-seeking rather than a deficit in nutritional literacy — they appear to know what constitutes healthy eating, yet consistently struggle to translate that knowledge into behavior. These findings emphasize the clinical necessity of integrating nutritional screening and targeted emotion regulation interventions into the multimodal management of adult ADHD to mitigate long-term metabolic morbidity and improve overall quality of life.

References

1. Erişkinlerde Dikkat Eksikliği ve Hiperaktivite Bozukluğu tanı ve tedavi kılavuzu. 2018, Ankara: Türkiye Psikiyatri Derneği Yayınları.
2. Simon, V., et al., Prevalence and correlates of adult attention-deficit hyperactivity disorder: meta-analysis. The British Journal of Psychiatry, 2009. 194(3): p. 204-211.
3. Kaisari, P., C.T. Dourish, and S. Higgs, Attention Deficit Hyperactivity Disorder (ADHD) and disordered eating behaviour: A systematic review and a framework for future research. Clinical psychology review, 2017. 53: p. 109-121.
4. El Archi, S., et al., Negative affectivity and emotion dysregulation as mediators between ADHD and disordered eating: A systematic review. Nutrients, 2020. 12(11): p. 3292.