TCS Daily

When an Ounce of Prevention Is Not Worth a Pound of Cure

By John Luik - August 17, 2005 12:00 AM

It appears to be all about science. After five days of WHO-think on health prevention at the Bangkok Global Conference on Health Promotion, it would be easy to conclude that science is the foundation for everything that the World Health Organization (WHO) does on health promotion. Wherever you look there are references to the scientific basis of health promotion and how everything that is done by WHO's health promoters meets the standards of modern medicine by being "evidence-based". But the scientific basis of WHO's health promotion is about as genuine and as sturdy as a Potemkin village. It makes impressive copy in all of WHO's conference press releases and it adds a veneer of respectability to the more controversial and dangerous of WHO's plans, but in reality it has little to do with real science or with medicine that is based on the evidence of best practices. That's because genuine science is fundamentally at odds with health promotion. Or to put it slightly differently, just as health promotion is a menace to the health of the developing world so it is a menace to real science. There are two reasons for this.

The first of these is that health promotion accepts if not encourages the manipulation and misrepresentation of scientific findings about the connection between health and lifestyle. Health promotion claims that by massive interventions by the public health community and the government into the "lifestyles" of ordinary people, the major diseases of the old in affluent societies can be prevented. As Gina Kolata, writing in the NY Times (April 17, 2005) observed. "The promises are everywhere. Sure, you smoked. But you can erase all those years of abusing your lungs if you just throw away the cigarettes. Eating a lot of junk food? Change your diet, lose even 5 or 10 pounds and rid yourself of those extra risks of heart disease and diabetes." But is this in fact true? Is there a scientific basis for the basic claim of health promotion that, for example, the two leading causes of death -- cancer and heart disease -- are the products of unhealthy lifestyles and that changing these lifestyles can prevent these diseases? Or are the promises of lifestyle change based on nothing more than hype?

The answer, which many will find surprising, is that after over fifty years of international data there is not good scientific support for the claim that lifestyle changes prevent diseases or increase longevity. Take, for example, one of the most extensive and publicized efforts in health promotion of all time, the Mr Fit (Multiple Risk Factor Intervention Trial) which was specifically designed to establish the truth of health promotion by showing that heart disease and cancer could be reduced through reducing blood pressure, cholesterol, and smoking. After sixteen years of study, the intervention groups, which had received extensive assistance with exercise, changing diet and smoking cessation, had results which were not significantly better than the group that had received none of these "health promotion" interventions. Indeed, the intervention group, despite lower rates of smoking, actually had higher rates of lung cancer. What MR Fit showed was precisely how lifestyle interventions failed to reduce mortality from multifactoral diseases like cancer and heart disease.

Nor was Mr Fit a scientific fluke. Consider the Framingham study. Begun in 1950 as a longitudinal investigation of the causes of cardiovascular disease, some 5,209 men and women aged 30-59 were followed for 30 years on the assumption that those who were thinnest would have significantly lower risks for heart disease. But in 1979 when three of the study's lead researchers published their data it was found that for men the highest risk -- that is the worst life expectancy -- was for the thinnest men; men who were 25-40% fatter than the ideal weight were living the longest. For women, mortality was elevated only for the very thin and the very fat. The recent Centers for Disease Control study on obesity and mortality produced similar results.

The reason for this lack of scientific support for lifestyle changes is to be found in the nature of the diseases about which we are speaking, and the fact that we know so little about them and how they might be connected with some particular aspect of how we live our lives. Both heart disease and cancer are multifactoral diseases, generally of old age, diseases that have multiple causes. For example, heart disease alone has over 300 risk factors that can be linked to lifestyle in thousands of possible combinations, while the etiology of cancer remains a mystery. To assume then that we can confidently tell people what life-style modifications can "prevent" cancer or heart disease is something much closer to propaganda than careful science. As Dr. Barnett Kramer of the National Institutes of Health told Kolata, people believe that if they change their lifestyle they can eliminate the damage and cheat disease because of the health promotion messages from the public health community and the government. "It is easy to overestimate based on the strength of the messages. But we're not as confident as the messages state."

At its very core, health promotion is a menace to legitimate science since it is prepared to fudge, force or fix whatever science says in order that it might serve the ends of promoting health. If you think this is too extreme a description of how health promotion views its relationship to science simply listen to Marc Lalonde, a former Canadian Minister of Health and founder of the health promotion movement, speaking about the relationship of health promotion and science. "...[T]he spirit of enquiry and scepticism, and particularly the Scientific Method... are a problem in health promotion." It's somewhat worrisome that the world's primary health organization, WHO, has embraced a health strategy for which science is a problem.

Health promotion is a menace to science in that it attempts fraudulently to use science to shut down debate about its demands for lifestyle change by claiming that its position is purely scientific and not open to any challenge on the basis of personal values or choice. Consider, for instance, the typical argument frequently advanced by WHO's health promoters against eating fast foods. The health promoter will claim that it is a scientific fact that if you stop eating fast foods you will live longer. (This is likely not true, but let's suppose it is.) Therefore you should stop eating fast foods. But this argument only works if another premise, a distinctly non-scientific premise is added, namely, IF you value living longer more than you value eating fast foods, then you should stop eating fast foods.

As soon as this premise is added the phony scientific character of health promotion is exposed for what it is -- a semantic trick that hides the value-laden and unscientific nature of the undertaking. Although it could be true that one could live longer if one eats less fast foods, it is not science that tells me that I ought to value living longer more than eating fast foods. In other words at its heart health promotion is completely unscientific: unscientific in the sense that its prescriptions are not backed by science and unscientific in the sense that they rest on the moral, not scientific premise that longevity is the prime moral virtue. This does not mean that the health promoter's injunctions about fast foods are unworthy of attention, though they probably are. It rather shows that they are not the pronouncements of science so much as someone's views about a particular way of living. This means that they must be justified like every other bit of moral philosophy about the good life through careful argument, not by spurious claims of scientific authority and the force of law.

At best then, the scientific foundations of health promotion extend only to its claims about the connection of disease and lifestyles, and these foundations, as we have seen, are highly dubious. When those in favour of getting the State involved in the lifestyle intervention business begin to speak about what to do about these claims, they cease to speak as exalted scientists and become simply moralists. And this has enormous implications for public policy that is founded on health promotion. When, for example, the health promoters at Bangkok tell us that we must all be thin, even if this involves the coercive powers of the state to "promote health", they must tell us -- and this they never do -- why a life of, say, 70 years packed full of the self-chosen pleasures of fast foods and chocolate is in some sense inferior to a life of 72.5 years without these pleasures.

This does not mean that 70 years crammed with fast foods and chocolate is necessarily better than 72.5 abstemious years. But it does suggest is that these are not scientifically mandated choices that the proponents of health promotion can make for the rest of us under the guise of "scientific decision-making" or "evidence-based medicine", so much as individual choices about the kinds of thing that we value and the sorts of life we want. Genuine science both understands and respects this. The "science" that drives WHO's Bangkok health promotion agenda does not, and because it does not it is a menace to us all.

John C. Luik is working on a book about health policy. He lives in Canada.


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