The paper reviews the so‑called “obesity paradox,” where people with diabetes and heart disease who are a bit overweight sometimes seem to have better survival than leaner patients. It points out that this may be due to study biases, the limits of BMI, and where fat is stored, rather than a true protective effect of extra weight.

The "obesity paradox" describes the counterintuitive observation that overweight and mildly obese individuals with cardiovascular disease (CVD) may have better outcomes than those with normal weight. This paradox is particularly intriguing in patients with type-2 diabetes (T2D), where obesity is a well-established risk factor for cardiometabolic complications. Evidence from some epidemiological studies suggested an obesity paradox in mortality risk among patients with T2D. However, confounding factors may influence this association, including reverse causality, differences in risk factor profiles, and adipose tissue distribution. Recent research also questions the reliance on body mass index as an accurate measure of metabolic health, emphasizing the role of alternative anthropometric indices. This review critically evaluates the evidence for the obesity paradox in T2D, explores potential mechanistic explanations, and discusses clinical implications. Understanding the complex interaction between diabetes and obesity in CVD risk is essential for refining obesity management strategies in individuals with T2D and CVD.