Modern public health policy can be capricious: “It’s the cure of the week or the killer of the week, the danger of the week,” according to Dr. Barry Kramer, Associate Director for Disease Prevention at the National Institutes of Health. Public health officials' endless regimen of “good food, bad food” whiplash and mandates based on health fads (trans fat bans, menu labeling laws, etc.) has raised an important question: Do they even know what makes the public healthy? The short answer is "Not really."

Unbelievably, many activists don’t seem to think this is a problem. In Sunday’s Chicago Tribune, public policy wonk David Michaels dismisses “demands for proof” directed at those who propose unsubstantiated laws: “Regulators don’t need certainty to act.”

Consider the potential damage of that notion, a blank check to legislate (and, ultimately, litigate) based on little more than circumstantial evidence. The effect could be devastating. Anyone familiar with the public-health track record of America's food police is all too familiar with damage wreaked by this “anything goes” approach to food policy. From milk to menus, dietary naysayers have demonized countless components of our diets, regardless of whether or not any evidence supported their claims.

Lawmakers, on the other hand, have a duty to the public to act with more (hopefully, much more) prudence. Though some proposals seem, superficially, to make sense, they could easily result in consequences far worse than the problem they aimed to fix. Last year, science author Gary Taubes explained to The New York Times the danger of justifying health policy with gross assumptions rather than concrete evidence: 

"From the public-health perspective, a small effect can be a very dangerous or beneficial thing, at least when aggregated over an entire nation, and so caution dictates that action be taken, even if that small effect might not be real. Hence the public-health logic that it’s better to err on the side of prudence even if it means persuading us all to engage in an activity, eat a food or take a pill that does nothing for us and ignoring, for the moment, the possibility that such an action could have unforeseen harmful consequences."

Thorough research prevents those “unforeseen” consequences by … well, seeing outcomes in advance through tests and experiments. It’s this burden of evidence that provides regulators with the certainty that they do need to act. Without it, culinary cops and self-anointed activists should take a step backward and let us enjoy dinner in peace.