“What are we going to do? Live on a diet of lentils and tap water?” That was the question posed by Chicago Tribune columnist John Kass during this morning’s Today show coverage of the Chicago City Council’s recent barrage of consumer constraints. Having banned foie gras, smoking on the beach, and poorly dressed taxi drivers (seriously), Windy City legislators have set their sights on trans fat — that oft-bemoaned fat you’ll find in all sorts of culinary delights.

Fortunately, Kass was there to inject some much-needed common sense into the debate. When pressed on the fact that a fitness magazine ranked Chicago as the fattest city in America, he responded, “Who cares?”

Most of us don’t. Our food decisions are our own and we’d like to keep it that way. But Alderman Edward Burke, a leading proponent of the trans-fat ban, is quickly becoming the Windy City’s chief food scold. And Burke believes that “if Chicago does this, every major city in the nation will do it. As Chicago goes, so goes the nation.”

One of the first rules of sensible policy discussions is to avoid making the “slippery-slope” argument … except when it’s handed to you on a silver platter. Having exercised regulatory power over one consumer issue, the Chicago City Council has now seen fit to do so with another. And another, and another, and so on — apparently hoping to inspire likeminded legislators across the country to follow suit.

What will be left to eat? Kass has an idea: “Lentils on a bun? I can’t wait.”