Margaret McCartney: Cancer patients should not be shamed

The charity Cancer Research UK has gone large on its publicity campaign about obesity. Bus stops and advertising hoardings are replete with black text on a white background. The adverts invite us to fill in the blanks and spell out OBESITY, asking us to “Guess what is the biggest preventable cause of cancer after smoking.”

The plain layout with warning label is reminiscent of a cigarette packet. I don’t think this is coincidental. In what Cancer Research UK itself describes as a “PR stunt,”1 the charity also created “fake cigarette packets with chips in to visually represent that obesity is the second biggest preventable cause of cancer after smoking.”

The effect of this has been somewhat predictable. Some people with cancer have told me that they have felt blamed. Other overweight people have written on social media of how they felt shamed.

Cancer Research UK says it has “tested the campaign and seen that it works.”1 It said its aim was to “raise awareness” of the link between obesity and cancer, and in doing so this would, it believes, allow it to have “better conversations” with MPs about “more change,” such as to “reduce junk food marketing.” The charity bases its belief on a pilot campaign in the West Midlands, the result of which, it told me by email, was that “awareness of the link increased by 22%.” But the data it sent me showed that, three months after the campaign, 27% of people exposed to it cited obesity as being linked with cancer, versus 25% in the control group. They have not proved that the campaign “works” in a meaningful way.

The charity has also said, as part of the campaign, that “being overweight or obese causes 13 different types of cancer.”2 But the vast majority of studies on this have found an association, not causation.3 We could argue that the hormonal effect of fat may contribute to some cancers’ origin, but patients and their families enduring cancer treatments and deaths do not need more confusion, guilt, and shame.

We need fair information. The risk of cancer from tobacco is a magnitude of between three and four times that of obesity, as Cancer Research UK’s own material shows. Combining the effect of eating more fruit and vegetables and less processed meat, for example, would easily outweigh the risk carried by obesity.4

And what of the harms of such campaigns? It is ironic that there is so little “awareness” of this. Unless we look systematically for the adverse effects of campaigns like this, we will not see them.

Guilt and shame cause misery and adversely affect health and care. I can understand this charity wanting to effect policy change. But it has not shown that this is the way to do it, and nor does it get to choose the effect of its campaign. We have evidence that people who are overweight are disproportionately harmed by weight stigmatising messages.56

We might reasonably ask whether this has been an evidence based campaign worth the harms.