Smoke screen

Smoking is under attack as never before. Today, the Government is expected to publish a white paper proposing restrictions on smoking in public places in England and Wales. Meanwhile, the Scottish Executive has agreed on a "comprehensive ban" on public smoking. Promoting the Scottish ban on the Today Programme, the country's deputy health minister, Rhona Brankin, declared "One in four of all deaths in Scotland is directly attributable to smoking." In a separate interview she said "one in four of all deaths (is) attributable to smoking. About 13,000 people die every year as a result of smoking." She was wise to omit the "directly" that sneaked onto Today.

Smoking is under attack as never before. Today, the Government is expected to publish a white paper proposing restrictions on smoking in public places in England and Wales. Meanwhile, the Scottish Executive has agreed on a "comprehensive ban" on public smoking. Promoting the Scottish ban on the Today Programme, the country's deputy health minister, Rhona Brankin, declared "One in four of all deaths in Scotland is directly attributable to smoking." In a separate interview she said "one in four of all deaths (is) attributable to smoking. About 13,000 people die every year as a result of smoking." She was wise to omit the "directly" that sneaked onto Today.

The most recent statistics reveal that 57,382 people died in Scotland in 2001. If one in four of them died for the reasons Rhona Brankin offers that would give a smoking-related death toll of 14,345, not 13,000. So is the minister guilty of modest exaggeration in the service of a noble cause? The one- in-four statistic is more than that; it is an article of faith among anti-smoking campaigners, but it is not as straightforward as it sounds.

These are not just lung-cancer deaths. Brankin's toll includes every Scot who has died of "smoking-related complaints." To get into that category alleged victims of smoking do not need to have smoked. They are counted in on the basis that killers including heart disease, strokes and bronchitis can be caused by smoking. Nobody checks the lifestyles of the victims to ascertain that they did smoke.

Some of these dead Scots did smoke, but died at or beyond the average Scottish lifespans of 73 years for men and 78 years for women. The same applies to many of the 140,000 English men and women whom the leading anti-smoking charity, ASH, asserts die each year as a result of smoking. ASH justifies including them on the grounds that deaths from smoking can follow years of painful disability and are thus worth preventing, even if they have not technically shortened a life.

The issue here is not whether smoking kills, but whether it is legitimate to lie in the service of a good cause. Amanda Sandford, the head of research at ASH, offers an intriguing response. "Smoking is the biggest single cause of preventable death, and anti-smokers do not deliberately abuse statistics. But I don't really want to be drawn into that. It isn't black and white." Pushed to explain precisely what she means, Sandford says: "Epidemiology is not a direct science. Our business is promoting public health. It is possible that in certain cases some anti-smoking campaigners do exaggerate [she is adamant that ASH does not] but if statistics lied it would be bad. There needs to be a justification for it. To deliberately distort would not be acceptable. If there is an element of doubt we should express that. Scientists usually express their statements in terms of caution."

She acknowledges that figures like Rhona Brankin's 13,000 deaths and ASH's 140,000 are sometimes "rounded up" but insists that any inflation is slight and is ironed out by annual variations in death rates.

ASH has excellent motives. The problem is that the degree of exaggeration that has converted hostility to tobacco from a health cause to a neo-religious crusade does not look slight when it is exposed to careful analysis. It has created a very misleading impression about the real chance of a smoker dying from lung cancer.

Habitual, lifelong smokers face a 30- to 40-fold higher risk of contracting lung cancer than non-smokers. That sounds massive and many smokers are persuaded to quit because they believe it is. But, since the risk of lung cancer in non-smokers is minuscule it does not amount to an objectively high risk. Amanda Sandford admits "Smokers are more likely to die of heart disease than lung cancer." The pro-smoking campaigner Joe Jackson argues "Even if you're a heavy smoker, your chances of NOT getting lung cancer are still more than 99 per cent."

Jackson's claim is based on Professor Sir Richard Doll's research on smoking and lung cancer. It calculated that 166 smokers in every 100,000 died from lung cancer. Subsequent research has proved that conservative. One doctor says "If you smoke 30 a day for 50 years you probably face a one-in-10 chance of developing lung cancer. It is a horrible way to die."

For that reason, the demonisation of tobacco companies as merchants of death does not offend me. Above the desk in the office where I used to smoke 15 cigarettes a day, until health concerns persuaded me to give up, hangs a reminder of the lies told in defence of a vicious business. It is a Camel advertisement from about the time of Professor Doll's ground-breaking report. Beneath the question "How mild can a cigarette be?", it asserts that there has been "not one single case of throat irritation due to smoking Camels" and supports this with the evidence of "noted throat specialists".

Cigarette manufacturers have murdered facts and perverted science to persuade consumers to continue smoking. When they first learnt that cigarettes killed, they responded by deliberately advertising preposterous claims about health benefits. Smokers of my father's generation were told that the habit eased digestion by increasing the flow of digestive juices and the alkalinity of the stomach.

But, as Scotland's devolved administration leads Britain towards a ban on the public indulgence of a dangerous but legal habit, it is worth recognising that the lies told by anti-smoking campaigners are substantial as well. Their intentions may be magnificent, but their tactics are not. If objective truth counts for anything then the title "merchants of sanctimony" is too generous. Anti-smokers have allowed their moral antipathy to smoking to distort their scientific advocacy. In private, many scientists and some doctors acknowledge this.

Dr Ken Denson, of the Thame Thrombosis and Haemostasis Research Foundation, says: "I simply do not know where they conjure up their statistics. The statistics for passive smoking, in particular, would not be published or even considered in any other scientific discipline. Deaths from smoking in general have been grossly exaggerated, particularly in relation to heart disease. " Dr Denson is a medical scientist. He has published peer-reviewed research in respected academic journals. He is not funded by tobacco companies.

Is he right? The method by which Rhona Brankin arrived at her "one in four" claim and from which ASH derives its 140,000 deaths categorises 16 diseases as "smoking-related". Many of them are also caused by poor diet, lack of exercise, obesity and other poverty-related problems that are regrettably common in urban Scotland and similar post-industrial areas. If you use cigarettes and are poor, fat and reluctant to eat vegetables, you are substantially more likely to die young than a smoker who is affluent, active and well-fed. "One in four" includes people who would have died when they did without smoking a single cigarette. It also includes affluent smokers who pass away from heart attacks in their late eighties.

The evidence that passive smoking harms health, on which the Scottish and UK governments both base their arguments for statutory restrictions, is even more inflated. Dr Denson, whose work on passive smoking has been published in the International Archives of Occupational and Environmental Health, says much of the evidence that passive smoking harms health "has been exaggerated, contrived, or at worst falsified". Even Amanda Sandford admits: "A lot of the studies that have been done on passive smoking produce results that are not statistically significant according to conventional analysis." But she still insists that passive smoking is a real health risk, made worse by the fact that it is involuntary.

There might appear to be no objective difference between overlooking conventional scientific method and deliberate distortion. But that is the problem with the modern debate about smoking. It is no longer conducted between good people who say that smoking kills and liars paid to deny it. Now it involves an industry that has, belatedly, been forced to admit that smoking kills and campaigners who are simply not satisfied with that. They want to convince the public that death is always the result and that every smoker and many non-smokers are at risk. They see no moral fault in lying to advance their case. Perhaps they are right and the end does justify the means. But I suspect their tactics may make the remaining minority of smokers still more determined to smoke. As one GP told me: "The danger of overstating a very real problem is that people always know anecdotal exceptions. They say, 'I ken Tam and he's smoked 40 a day since the battle of Narvik and never had a day ill in his life.' We might do better to admit that people like that exist, and even to speculate about why. That would lend authority when we point out the real risks."

The willingness of militant anti-smokers to corrupt a good case has turned the smoking debate from a laudable campaign to improve public health into a bitterly resented attack on the minority who choose to risk smoking. One medical researcher says: "Statistically the evidence for the evils of smoking has been grossly distorted. For many people the ideal of a complete end to smoking has become a sort of Holy Grail with a limited basis in fact. More of us would say this, but it is politically unacceptable to speak the truth about these things." He suggests that rabid anti-smokers should look at the prevailing rates of smoking among young people born after the relationship between smoking and cancer was admitted by the tobacco industry - and remind themselves what happened to the boy who cried wolf.