Back when Jaws was scaring us on the big screen in the 1970s, Americans were being warned of a more subtle danger. On television and in the papers, we were told that saturated fats, the type found in some meat and dairy products and in some processed foods, were on the verge of causing an epidemic of heart disease.
Though our knowledge about the risks associated with saturated fats was limited and information about alternatives even less developed, the country took action. In the years since, saturated fats -- which are tasty, stable, and solid at room temperature (a characteristic that makes them valuable for food processing) -- have been replaced with the only alternative that served the same function. You may have heard of it, since it's been in the news lately: trans-fat. This big change in the way we ate came to us thanks to food police and their favorite weapon, the precautionary principle.
The principle, sometimes benignly known as "better safe than sorry," states that "when an activity raises threats of harm to human health or the environment, precautionary measures should be taken even if some cause and effect relationships are not fully established scientifically." An unstated corollary is "Precaution should be taken regardless of the risk of any precautionary action." That is, trying too hard to err on the safe side can lead to doing something less safe. This explains why Michael Crichton wrote in State of Fear: "The 'precautionary principle,' properly applied, forbids the precautionary principle. It is self-contradictory."
As a result of the campaign against saturated fats, manufacturers switched to trans-fats, and those of us who wanted to be healthier switched from butter to margarine. Yet now, with only the weakest case against trans-fats, it too is put on the no-no list. In fact, the chairman of the Department of Nutrition at the Harvard School of Public Health, Dr. Walter Willet (who, in an unfortunate irony, holds a professorship named after ACSH co-founder Dr. Fredrick Stare), told the New York Times, "When I was a physician in the 1980s, that's what I was telling people to do [switch from saturated fats to trans-fats], and unfortunately we were often sending them to their graves prematurely."
This is a result of rushing to lower a perceived threat before accurately gauging the effects of such a change. In this case, people rushed to replace saturated fat with trans-fat, before we really understood what effects such a substitution might have. All those consumers who made the switch and sacrificed butter for margarine are now being told that the effort may have done more harm than good.
In reality, they probably did no harm, but they did no good, despite their best intentions. They would have been better off listening to more scientifically well-established health advice, like that found in ACSH's New Year's Resolutions. (But at least when these people had their lives altered by the precautionary principle, they were only mildly affected. Not everyone is so lucky. Witness the millions of victims of malaria since Rachel Carson's Silent Spring inspired governments to ban DDT "just in case".)
In spite of doomsayers' warnings, there's no substantial body of evidence that trans-fats have killed anyone. In fact, for multiple and complex reasons, over the period when trans-fats came into common use, rates of deaths from heart disease have actually dropped. The evidence on trans-fats doesn't seem to justify the rush to purge every ounce of it at any cost. Once again, those who applied the precautionary principle by telling us to eat margarine instead of butter -- "just to be safe" --might now be sorry.
Jeff Stier, Esq., is an associate director of the American Council on Science and Health.