Scoping Literature Review: The Role of Leptin in Autism Spectrum Disorder (ASD) and Associated Obesity

Overweight and obesity (OW/OB) are significant concerns among individuals with Autism Spectrum Disorder (ASD), yet the underlying causes remain unclear. Emerging evidence points to metabolic and hormonal factors—particularly leptin, a hormone involved in appetite regulation—as potential contributors. This scoping review examined five key studies from 2003 to 2024 that investigated the relationship between leptin and ASD in overweight populations. Across studies, individuals with ASD consistently exhibited elevated leptin levels compared to controls. While some findings also noted changes in other adipokines, such as lower resistin or progranulin, leptin was the most consistently dysregulated. These patterns suggest systemic alterations in energy metabolism or inflammation in ASD, though results are limited by small sample sizes, heterogeneous study designs, and unaccounted confounding variables like medication use and physical activity. The literature reveals a strong association between elevated leptin levels and ASD, but the underlying mechanisms and clinical implications remain unclear. Leptin dysregulation may contribute to obesity in ASD either through impaired satiety signaling or leptin resistance. Future research should focus on larger, more diverse populations and consider hormonal, behavioral, and lifestyle factors. To further explore this relationship, I plan to collect leptin data from neurodiverse patients at the RISN Center at Rowan-Virtua. Whether leptin is found to be low or high, both scenarios could help explain the high prevalence of obesity in this population and potentially guide targeted interventions.