Junkfood Science: The greatest myth of health risk factors

May 07, 2007

The greatest myth of health risk factors

Why do studies continue to find that health risk factors don’t actually predict who will succumb to disease or die early? Why do people with a wide range of numbers (body mass index, blood lipids, blood sugars, blood pressures), diets and lifestyles end up dying around the same time and of the same things? Why don’t risk factors make a bigger, sure-fire difference?

The answer comes down to what we’ve been misled to believe about risk factors. These misconceptions are the key to successfully scaring us about our health, food and life; the key to compelling us to do things proactively “for our health” that don’t really make all that much difference; and the key to identifying and blaming “bad” people, foods and lifestyles.

If there was one thing, and only one thing, that could most help people by understanding, it would be risk factors.

Armed with this knowledge, fewer people would be needlessly frightened, manipulated, taken advantage of, and hurt. We could feel freer to live our lives without surrendering to the constant anxiety that surrounds us. There would be no need to live in perpetual fear that one misstep might mean something bad will happen. We would be able to actually feel healthy and realize that we really are! And everyone could fully enjoy the glorious variety of foods, bodies, cultures and lifestyles that make human life rich and meaningful.

That probably sounds melodramatic because most of us believe we understand risk factors perfectly well. Let’s take a moment to critically think about them.

Are brown eyes a disease or do they cause a disease?

Are yellow teeth a disease or do they cause a disease?

Are funny ear lobe creases a disease or do they cause a disease?

Is gray hair a disease or does it cause a disease?

And might colored contact lenses, teeth whitener, plastic surgery or hair dye therefore prevent disease?

The answer to all of the above is: “Of course not!”

Yet, all of these things are health risk factors. Brown eyes are a risk factor for night blindness. Yellow teeth are a risk factor for lung cancer. Funny ear lobe creases are a risk factor for heart disease. And gray hair is a risk factor for just about everything.

Instead, this probably sounds truer to us: “High cholesterol and hypertension are diseases, obesity is a disease, and all of them cause or contribute to even more horrible diseases. Not to mention, fatty or sugary foods spell certain ill-health.”

Why are we more apt to believe these and not the first ones? There’s certainly a lot more money in selling us a lifetime of pills, endless diets and bariatric surgery, “health” food and supplements, wellness programs, and public health programs and regulations; than there is in a bottle of hair dye, contact lenses, teeth whitening or a one-time little ear tuck. But the first ones are little better or worse than other risk factors, nor is the actual evidence to support them appreciably different. Yet, if we applied the same logic as we believe about more popularized risk factors, we would have to believe all of the above.

Dr. Malcolm Kendrick, Medical Director of Adelphi Lifelong Learning, Cheshire, UK, estimates that about 1,000 risk factors have now been identified for heart disease. And there are countless numbers for cancer. Just about everything, it seems, can cause cancer. Wearing a bra is a risk factor for breast cancer, wearing boxers a risk factor for prostate cancer, and eating (anything!) is a risk factor for most everything. Consuming a lot or too little garlic, red wine, chocolate, fat, red meat, whole grains, sugar, or produce; and having migraines, bad teeth, pot bellies, dark skin and big noses — have all been made a risk factor for something. And they’re sure to change tomorrow. It’s little wonder that we’re all nervous wrecks.

What’s there not to be worried about?

Risk factors.

Yes, the evidence for the importance we place on risk factors consistently falls short, despite our growing anxiety over them. This mass fear is the result of consumers and a surprising number of healthcare professionals misunderstanding the meaning of “risk factors.” Let’s start by what risk factors are not.

· Risk factors are not the same as risks.

· Risk factors are not the same thing as a disease.

· Risk factors do not cause disease.

· Risk factors can't be said to contribute to diseases, and having more doesn’t make you more diseased.

All that the term “risk factor” means is that a researcher has found a correlation between two variables. We get risk factors from epidemiology. And it’s easy to take a group of people and pull out endless correlations between those with and without some disease and produce another health “risk factor.” And something else to scare us with.

And what is the fundamental principle of correlations? Correlations are not causation. Correlations often contradict each other, and make for downright silly conclusions or advice. Remember this one? — “Women, rack up those frequent flyer miles to lower your risk for miscarriage!

Being Black is a risk factor for sickle cell anemia but skin whitening won’t do a thing to prevent or cure sickle cell anemia. And “being male is now the single largest demographic risk factor for early mortality in developed countries,” according to Daniel Kruger, a social psychologist at the University of Michigan Institute for Social Research. Yet, eliminating men from our population isn’t the way to solve that one, either!

Correlations from data dredge studies are useless by themselves — no matter how strong or intuitively correct they might seem, like those vitamin studies in this post — until they’ve been demonstrated in clinical trials on actual people to mean something. But few people realize a risk factor is just a correlation. We’ve been sold.

The mythology of risk factors for common diseases like heart disease and cancer have proven an incredibly fertile technique for generating a steady stream of false scares. Every day brings news of something else to be worried about and we’re constantly told by experts that our health is endangered by some new risk factor. It’s proven inordinately successful in making growing numbers of us worried sick about our health. The common sense advice of the past: “don’t smoke and enjoy a variety of foods” has mutated into denunciation of practically everything in life. It’s gone far beyond what any credible evidence can support.

As Dr. James LeFanu, M.D. wrote in The Body Politics:

So mouthwashes have been implicated in oral cancer, aluminum saucepans have been associated with dementia, keeping cats with multiple sclerosis, alcohol with cancers of the breast and oesophagus, coffee with cancer of the pancreas, sun exposure with skin cancer, and a high-fat diet with virtually everything. This technique is so fertile that for one illness alone, coronary heart disease, there are now no less than 240 personal risk factors [which have grown to 1,000 since he wrote this] which range from not eating enough garlic to being bald, from having an intelligent wife to having an unloving one, from drinking too much milk to drinking too little, from coffee and chlorinated water, and so on, and on and on. These “risk factors” are for the most part shallow and contradictory, but that does not matter because, like the never-ending drip of water on a stone, they penetrate the public consciousness, engendering the belief that our everyday habits are treacherous and that virtually anything can harm someone.

Lest anyone be skeptical about these hazards, the public health police guarantee the validity of their findings by means of evoking the authority of “expert committees”. These committees, carefully selected to exclude anyone who might have “doubts”, gather round a table, ostensibly examine the entrails of the scientific evidence and then, by a show of hands, assert the certainty of the threat.

Remember: a risk factor is just a correlation.

Even the term “disease” increasingly doesn’t refer to actual clinical illness or disability anymore. Some want us to believe that certain risk factors themselves are diseases, too. [Although this is inconsistently applied, depending on whatever is popular to believe or is being sold. While, for instance, the most “morbidly obese” women (the upper 0.2% of the population, even) live longer than normal weight men, obesity is declared a disease, but maleness isn’t!]

Normal diversity found among a population has become medicalized and those falling outside of arbitrarily-determined “ideal” thresholds are seen as diseased. While any extreme of a health indice, such as cholesterol, could be an indication or marker that something might be amiss and real extremes might be life-threatening, that doesn’t make high or low cholesterol itself a disease or mean that by keeping our cholesterols at some perfect sweet spot we can prevent disease or premature death. The mid-ranges in values where most healthy people fall don’t make appreciable differences in actuality. Same goes for body size, blood pressures, blood sugars, etc.

Nonclinicians, however, are easily swayed into believing that for most health indices there’s some ideal number where health is optimal and risks of dying are averted. Certainly, those beliefs are what’s behind employer wellness programs which base compliance on ideal risk factor numbers; and the pay-for-performance measures doctors are increasingly obligated to treat in order to receive compensation from insurers. But as Dr. Rodney A. Hayward, M.D., professor of Medicine and Public Health at the University of Michigan, Ann Arbor, and director of the VA Ann Arbor Health Services Research and Development Center, explained in the March issue of the American Journal of Managed Care:

This point of view shows a lack of understanding of epidemiological evidence....in most instances, the risks associated with deviations from optimal goals follow an exponential pattern (so that small deviations from treatment targets are often of little importance); and because most medical treatments have side effects, risks, and costs, pursuing minimal deviations from idealized goals will often involve speculative care that is not worth the cost and may expose patients to undue risks and burden.

The public has been convinced, however, to give risk factors such importance that it’s affected our very concept of what it means to be healthy. Rather than realize that most of us are healthy most of the time and only occasionally get sick and then get better again; it’s become widely believed that healthy young people need regular medical attention and constant diligence to stay healthy because we’re all at risk. While health promotion — i.e. healthy eating, exercise and healthy indices — has become firmly entrenched in popular consciousness, this belief “marks the triumph of the ideology of health promotion,” said Dr. Michael Fitzpatrick, a general practitioner in Hackney, London and author of The Tyranny of Health— doctors and the regulation of lifestyle.

Preventive health screenings and intervention involve intervening in the lives of masses of well people in the hope of preventing diseases among a few, he said. Yet these measures can have bad consequences for some, while not really benefiting many of the few, some of whom will still succumb to the disease, said Dr. Fitzpatrick. While widening ranges of diseases are being addressed and massive amounts of healthcare resources are poured into preventive health and wellness programs, real health needs, especially among the elderly and poor, are neglected, he said.

The simple expedient of closing down most university departments of epidemiology could both extinguish this endlessly fertile source of anxiety-mongering while simultaneously releasing funds for serious research. — Dr. James LeFanu, M.D. (The Rise and Fall of Modern Medicine)

Just this morning, Dr. Ned Colange, M.D., chairman of the U.S. Preventive Services Task Force addressed the worried well and cautioned CBS Morning News viewers that seeking unnecessary screening tests and unnecessary treatments that they don’t need is harmful.

Remember: risk factors are just correlations.

The misuse of epidemiology to identify behaviors, diets and lifestyles that we’re told contribute to disease and premature death has become a familiar misuse of “risk factors.” Correlations surrounding lifestyles have been twisted into causations and been used to convince us that health is a matter of personal responsibility under our control, to blame people when something goes wrong, and to make people feel incredibly guilty about any health problems they do develop and others to feel virtuous when they don’t. As Paul R. Marantz of Albert Einstein College of Medicine, New York, wrote in the American Journal of Public Health:

The misleading message that an individual will prevent a particular disease by altering a particular behavior or exposure (and its converse, than an individual will develop a particular disease if such behavior is not changed) has unfortunately been widely conveyed.

The sad fact of the matter is that beliefs and fears surrounding risk factors defy the reality of human biology, undermined our confidence in our bodies, and have left us all feeling weak and vulnerable, at risk of falling ill at the slightest exposure. As Dr. LeFanu wrote in an article, “The Fall of Medicine:”

[O]ver the past 20 years, statistical associations have implicated almost every aspect of people’s everyday lives in some lethal disease or other....But most of these alleged hazards, about which we read everyday in the newspapers, cannot possibly be true. The human organism is — as it has to be — robust and impervious to small changes in the external world. The notion that subtle alterations in patterns of food consumption or undetectable levels of pollutants can be harmful is contrary to the fundamental laws of human biology.

How else could the human species have survived to this point? The credibility of science and the medical profession, and the public’s trust in both, has been undermined by these abuses of epidemiology, Dr. LeFanu argues:

Rather, the social theory has had the regrettable consequence of undermining medicine's reputation as a source of reliable knowledge. When Frank Dobson, the health minister, warned...that anyone eating three lamb chops a day or its equivalent was at increased risk of cancer, medical authority became indistinguishable from quackery.

The same could be said about recent studies equating the supposed deadliness of a single teaspoon a day of transfats to a 9-11 every year; or that a single donut or serving of chips can harm a woman’s chances of having a baby, or that normal salt intakes cause 25% of all heart attacks and strokes.

Remember whenever you hear the term, risk factor, that it is just a correlation, not a disease, a measure of actual risk, or cause of death.

The biggest risk factor for the diseases that eventually kill all of us is aging. And there’s not much we can do about that one, no matter how much some may want us to believe otherwise. Everything else pales by comparison. In the meantime, less panic and fear, and a lot more balance and common sense, can help all of us get the most out of the lives we have.

© 2007 Sandy Szwarc

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