Is There a Crisis of Overdiagnosis in Modern Medicine? With Dr Suzanne O’Sullivan

In this episode of Intelligence Squared, Dr. Ganesh Taylor hosts Dr. Suzanne O'Sullivan, a neurologist and author, to discuss her book *The Age of Diagnosis* and the growing crisis of overdiagnosis in modern medicine. O'Sullivan argues that while medical labels can provide validation and explanation, they often fail to lead to meaningful treatment or improvement—especially in cases of mild or atypical symptoms. Drawing from her clinical experience, she highlights how diagnoses, particularly genetic ones like Huntington’s or Alzheimer’s risk, can cause psychological harm by amplifying normal bodily changes into perceived illness. She warns that the increasing availability of tests and self-tracking technologies has led to a culture of health anxiety, where people seek diagnoses not for treatment but for certainty, often at the cost of their mental well-being. The episode emphasizes that the value of a diagnosis lies not in the label itself, but in what it leads to—treatment, relief, or support—and urges listeners to question whether a diagnosis truly serves them. O'Sullivan advocates for a return to patient-centered care, where clinical history and doctor-patient relationships take precedence over an overreliance on tests. She stresses that medical tests are not neutral—they are context-dependent and can create new problems by revealing incidental findings that increase anxiety. She encourages people to prioritize lifestyle prevention over unnecessary testing and to recognize that being healthy doesn’t require constant monitoring. Ultimately, the episode calls for greater agency in healthcare: to seek help without labels, to value the doctor’s judgment over data, and to understand that not every symptom needs a diagnosis—and sometimes, not knowing can be a form of protection.