I’m against overdiagnosis, overcooked food, and over long films, said David Haslam, chair of the National Institute for Health and Care Excellence.

All of us probably agree—especially when it comes to overcooked food—which is part of the problem.

At the Preventing Overdiagnosis conference in Oxford, the big topics are diabetes, hypertension, and statins. Lifestyle diseases that we are regularly treating, with the aim of reducing incidence, even where treatment will make very little difference to individual patients.

Two recent articles in The BMJ have tackled these big topics: Stephen Martin et al looked at mild hypertension, and John Yudkin and Victor Montori considered pre-diabetes. Both talked about how tinkering with the thresholds for diagnosis, and extrapolating treatment efficacy from more severe cases, has led to a massive expansion in the number of patients being medicalised.

For me, these arguments still seem abstract. The standout figure is that out of 100 patients treated for mild impaired glucose tolerance, 95 will not experience any benefit from that treatment. That figure bears repeating, 95 out of 100.

As Yudkin said at the meeting, there is no herd immunity with these interventions, no glow of selflessness to be had in knowing that by choosing to take these medications there is gain to the wider population. Yet we ask patients to take them, we encourage—even force—GPs to test and treat through the Quality and Outcomes Framework. And I can’t help feeling that I, as a current non-patient who is heading towards these interventions, would not want any of this.

So what is driving this? Mea culpa, the audience suggested, we are overzealous in trying to protect our patients. Or else, look to commercial medicine (pharma or for profit screening companies). But I wonder if the answer lies more in some of the preliminary research presented at the conference, which questioned what patients know about the phenomenon of overtreatment and overdiagnosis. Ray Moynihan has asked lots of patients if they understand these terms, and the bottom line is they don’t. And for the majority, their doctors haven’t explained it to them, even if they have undergone screening for breast or prostate cancer.

Improving the public’s understanding of overdiagnosis is going to be a long slog. As David Haslam said, there are no amazing stories of the footballer on the field who never had a heart attack because public health initiatives stopped it. The complexities of the arguments, and the uncertainty that underpins many of the overdiagnosis analysis articles we publish, are difficult to turn into soundbites. But if NICE’s mandate to doctors (that “treatment and care should take into account patients’ individual needs and preferences . . . Patients should have the opportunity to make informed choices about their care”) is to be followed, then it will be necessary to help the public understand.

So where does that leave a patient, if they reject the medicalisation of their possibly slightly elevated risk of a condition? Perhaps it’s, as Muir Gray suggests, actually a case of underdiagnosis—do you have Walking Deficiency disease? The common thread to these lifestyle diseases was that there is good evidence for the benefit of lifestyle changes, and that patients have to take responsibility for their health through the choices they make about food and exercise.

Duncan Jarvies is multimedia producer for The BMJ.

Read Helen Macdonald’s blog on this conference: Too much medicine—not a NICE business