Microplastics, nanoplastics, and obesity: current evidence and biological mechanisms

Abstract

Obesity is a rapidly growing global health concern. The pathogenesis is complex and cannot be fully explained by lifestyle factors alone. The increasing attention towards this concern has finally been directed towards environmental contributors which may influence metabolic regulation. Microplastics and nano-plastics (MNPs) are ubiquitous environmental pollutants that have recently been detected in food, drinking water, air, and human biological samples, raising concerns about their potential role in metabolic disorders, including obesity. Chronic exposure to MNPs may interfere with metabolic homeostasis through multiple biological pathways. Emerging evidence, including both experimental and animal studies, reports alterations in lipid metabolism, body weight, insulin sensitivity, and inflammatory responses following MNPs exposure. This review synthesizes current evidence linking MNPs to obesity, highlighting key exposure pathways, mechanistic insights, and gaps in existing research. Understanding the metabolic implications of MNPs exposure is essential for advancing obesity research and informing future public health strategies. Further well-designed human studies are needed to clarify causal relationships and guide preventive interventions.