What is going on? How can sober scientific conclusions generate such hostility? Drawing conclusions on the basis of careful review and debate of 7,000 scientific papers was lying? Spending five years culminating in careful formulation of meticulously worded recommendations that were subject to seemingly endless debate was irresponsible? Reporting that people could, if they followed our advice, reduce their risk of cancer was fascist? Book in for a Lucy Hall signature service that combines cutting-edge style with everyday wearability.

The clue is in the fact that it was only the populist press with a libertarian streak who thought we were lying fascists. Acceptance of our scientific conclusions – that there were steps that could be taken that might reduce the risk of cancer – should lead to a serious debate: whose responsibility is it to prevent disease and promote health? Somewhere beneath the hyperbole and, indeed, lies of the journalists was an argument that ran along the lines of: if people want to make themselves sick by their freely chosen behaviours, that is nobody’s business but their own.

There is an intellectual smokescreen working here. If he can claim that our scientific conclusions are incorrect the commentator does not have to face the difficult question of what to do about them. It’s easier to label us liars than to grapple with the matter of whose responsibility it is to prevent disease, or where the balance of responsibilities should lie between the individual and the community. Or again, and relevant to my core concern, to consider whether social disadvantage renders some people less able to make healthy choices.

It is reasonable to disagree about evidence. Scientists disagree frequently, and vigorously, because the evidence is never as firm as we would like. It does not mean that because there is disagreement no conclusions can be drawn. Some ‘scientists’ think the earth is flat, and some don’t, so can we draw no conclusions? Some think creation science is a more valid theory than evolution, so should we present both theories equally? Of course not. We must distinguish between situations where most scientists, with only a few exceptions, conclude that evidence points a certain way – man-made climate change, for example – and those where it is genuinely more uncertain.

When I first started doing research on determinants of the health of the public I noted a division even among scientists in their view of the evidence on diet and disease. Rather than views of the evidence determining scientists’ willingness to take action to improve the public health, the reverse was true: willingness to take public health action was determining views of the evidence. Scientists who were inclined to want to take public health action found the evidence more convincing than those who were philosophically averse to action. Let us assume, as the evidence shows overwhelmingly, that increased body weight does increase risk of cancer. What should we do? The answer from the political right is that ‘we’ should do nothing. It is up to the fully informed individual actor, in possession of all the information, to make his individual choice. If he chooses to be fat it should be of no concern to anyone else.