ADHD as a System Disorder: A Narrative Review of Genetic, Nutritional, Psychological and Environmental Interactions
Keywords:
ADHD; nutrigenomics; micronutrients; gene–diet interaction; MTHFR; dopamine; pseudo-ADHD; FADS2; folate; omega-3; inflammation; IndiaAbstract
Purpose: Narrative review was conducted to identify, critically appraise, and summarize the current findings on Attention-deficit/hyperactivity disorder (ADHD) and interaction between nutrient status, gene polymorphisms, and environmental exposures in the development and progression of ADHD The review also explores the emerging concept of pseudo ADHD and addresses region-specific challenges, particularly within low- and middle-income contexts such as India.
Materials and Methods: Search was conducted using databases including PubMed, Scopus, and Google Scholar. Articles published between 2000 and 2024 that relevant to ADHD, nutrigenomics, micronutrient deficiency, dopamine regulation, pseudo-ADHD, and public health. A total of 110 unique sources were reviewed, including genetic studies, clinical trials, meta-analyses, and population health reports.
Results: Systematic reviews including individual meta-analyses were included in the umbrella review reporting strong evidence that variants in genes like MTHFR, SLC6A3 (DAT1), FADS2, and DRD4 influence neurodevelopmental trajectories by affecting methylation, fatty acid metabolism, and dopamine signalling.
Conclusion: Strong evidence supports that these genetic susceptibilities are modulated by dietary intake of folate, zinc, iron, and omega-3 fatty acids. Environmental factors—such as sleep disruption, excessive screen time, and ultra-processed food consumption—may lead to behavioural phenotypes that mimic or amplify ADHD symptoms. Indian children are particularly at risk due to the coexistence of undernutrition and modern dietary shifts.
