A doctor’s brilliant study of the dangers of overdiagnosis, from ADHD to long Covid

We swim in oceans of quackery. The media is flooded with misinformation about health and pseudo-diagnoses based on vibes rather than evidence. Books awash with error and supposition swamp our charts, penned by people uniquely unqualified to write them. Our ears are filled with popular podcasts claiming health benefits but really just peddling unregulated dietary supplements. And Robert Kennedy Jr, a man who has spent a lifetime spewing antivaccine jibber-jabber, is now US secretary of health. Vaccination is arguably the most successful health intervention in history (with the possible exception of sanitation), and now more than ever we should be basking in the fact that a global pandemic was brought to a close by safe and effective vaccines.

But here’s the conundrum: medical diagnoses are on the rise across the board, in many cases dramatically, and this is fuel for the medical disinformation industry. The most obvious example is autism, the incidence of which has shot up in a couple of decades, correlated with, but not caused by, an increase in vaccination. Cancer diagnoses are also up. A lot more people seem to have ADHD these days, which was barely around when I was at school. And millions now endure long Covid, a disease with a bucket of symptoms that did not exist at all five years ago.