Obesity — the major groups of its complications

Background: Obesity has evolved from a simple metabolic condition into a complex, chronic systemic disease that has reached pandemic proportions in the 21st century. It serves as a primary driver for a multitude of chronic pathologies across virtually every human organ system. Aim: This narrative review aims to provide a comprehensive analysis of the major groups of obesity complications, exploring their pathophysiological mechanisms and epidemiological impact across the lifespan, with a focus on pediatric development and geriatric well-being. Material and methods: A systematic search of PubMed, MEDLINE, Google Scholar. Selection criteria prioritized peer-reviewed articles, meta-analyses, and cohort studies published between 2014 and 2026, focusing on the mechanisms of metabolic, cardiovascular, respiratory, musculoskeletal, and psychosocial impairment. Results: Metabolic complications of obesity include type 2 diabetes and hyperuricemia, while cardiovascular effects range from hypertension to coronary artery disease. Respiratory health is compromised by mechanical and inflammatory pathways, leading to obstructive sleep apnea and hypoventilation. Pediatric studies demonstrate that excessive weight significantly accelerates skeletal and dental maturation, while geriatric data highlight severe declines in self-esteem and social integration. Conclusions: The complications of obesity are intrinsically linked to chronic low-grade inflammation and hormonal dysregulation. Management must move beyond simple weight loss to address the systemic inflammatory environment and the varied psychosocial consequences.