Understanding Insulin Resistance in Obese Adults During Midlife: A Review of Prevalence, Pathogenesis, and Clinical Outcomes

Insulin resistance (IR) constitutes a pivotal mechanism linking obesity to cardiometabolic diseases, with particular salience in middle-aged adults where cumulative lifestyle exposures converge with age-related physiological declines. This cross-sectional review synthesises contemporary evidence on IR prevalence, determinants, and correlates in obese individuals aged 36-55 years, aggregating data from global cohorts and meta-analyses published through 2025. Pooled analyses reveal IR prevalence exceeding 60%, driven by visceral adiposity and inflammation, underscoring imperatives for enhanced screening and multifaceted interventions to avert progression to type 2 diabetes mellitus (T2DM) and cardiovascular events.