The San Francisco Chronicle wisely used today’s editorial page to question the merit of the city’s impending menu labeling policy: “It seems the saying ‘the customer is always right’ rarely applies in San Francisco City Hall, where government thinks it knows best.” The gaping holes in the logic of this latest foray into Big Brother lawmaking should lead Golden Gate residents to question not if City Hall knows best, but if it knows anything at all.

Despite its intense focus on counting (calories, fat, salt, etc.), menu labeling just doesn’t add up.  Americans only eat one-fifth of our calories at restaurants. Targeting less than 300 of the city’s 5,369 restaurants, Supervisor Tom Ammiano’s bill narrowly focuses on an even smaller piece of the calorie pie. Consequently, the proposed policy may impact as little as one percent of the average San Franciscan’s diet—a mere 20 calories per day.

On the other hand, the biggest chunk of the food we eat—66 percent of our calories—comes from groceries prepared at home. And nutrition labels haven’t curbed our eating habits there.

With an unproven measure that targets only a tiny fraction of our food intake, nutrition activists simply cannot justify the imposed costs and possible unintended consequences of menu labeling. Health experts fear that government-mandated calorie counts and other anti-obesity policies may be doing more harm than good. Last week, the London Times addressed this very issue in its educational supplement:

Organizations specializing in eating disorders worry that the focus on young people’s weight—and the way some adults demonize certain foods—is creating a generation obsessed with growing fat and increasingly guilty about eating.