The Obesity-Heart Disease Connection: Is Weight Loss the New Cardiovascular Prevention?
Obesity affects more than one billion people worldwide and is a major upstream driver of cardiovascular disease (CVD). Dysfunctional visceral adipose tissue acts as an active endocrine organ, promoting insulin resistance, lipotoxicity, systemic inflammation, and neurohumoral activation. These pathways link excess adiposity to a cardiometabolic continuum that includes type 2 diabetes, hypertension, heart failure with preserved ejection fraction (HFpEF), atrial fibrillation, and atherosclerotic cardiovascular disease. Recent cardiovascular outcome trials have moved obesity treatment from a lifestyle goal to an evidence-based strategy for cardiovascular risk reduction. In SELECT, semaglutide 2.4 mg reduced major adverse cardiovascular events by 20% in adults with overweight or obesity and established CVD without diabetes, leading to FDA approval for this indication in 2024. In obesity-related HFpEF, semaglutide improved symptoms and functional capacity in STEP-HFpEF, and tirzepatide reduced the composite of worsening heart failure events and cardiovascular death by 38% in SUMMIT. These benefits likely reflect both weight loss and weight-independent effects on myocardial metabolism, inflammation, natriuresis, and epicardial fat. In this Perspective, we review the mechanisms linking obesity to CVD, summarize key incretin-based outcome trials, and argue that sustained intentional weight loss, whether achieved through lifestyle intervention, pharmacotherapy, or metabolic surgery, should be recognized as a core component of cardiovascular prevention, with success measured by the prevention or resolution of obesity-related CVD rather than by weight change alone. Cost, inconsistent insurance coverage, and weight regain after discontinuation remain substantial barriers, and ongoing primary prevention trials such as SURMOUNT-MMO will determine whether these benefits extend further upstream.