A paradox or a challenge?

Sepesi et al. (1) found in a large retrospective series that higher body mass index (BMI) was associated with improved overall survival in patients undergoing surgical resection of non-small cell lung cancer (NSCLC). Is this a paradox? “Paradox” is a rhetorical, not a scientific, term (2). Unfortunately, the term obesity paradox has entered into the medical vocabulary while simultaneously becoming less and less clearly defined. By now, the term is used to refer to almost anything that suggests improved outcomes associated with obesity. The underlying assumption is that any better outcome related to obesity is ipso facto surprising and counterintuitive and thus considered a “paradox”.