Today, San Francisco’s bureaucrats will vote on a proposed menu-labeling ordinance, requiring popular chain restaurants to cover their menu boards with inescapable calorie counts.  Proponents of the measure have already tried and failed to implement the ordinance statewide. So now they’ve adopted a divide-and-conquer strategy, stripping Californians of their right to guilt-free eating one city at a time.

In today’s San Francisco Chronicle, radical nutrition activist Harold Goldstein, executive director of the California Center for Public Health Advocacy, betrayed a common food cop double standard. Goldstein claimed that the menu mandate is justified because “what we don’t know can - and will - hurt us,” but the policy itself is a prime example of “what we don’t know.” There’s no evidence that menu labeling improves people’s eating habits. In fact, research shows that nutrition information often backfires, giving consumers justification to eat more than they normally would. And that could definitely hurt us.

Requiring a calorie catalogue on restaurant food also faces a fundamental problem. It assumes that our growing waistlines are the result of too many “calories in” rather than too few “calories out”—an unfounded assumption. The National Weight Control Registry, the group that tracks thousands of Americans who have effectively lost and kept weight off for more than a year, finds no single formula for success among its members’ eating habits. The only common denominator is physical activity.

While there’s no proof that labels on menus cause any weight loss, research has found that “fitness labeling” can make a difference. One study found that posting a sign alerting shoppers that “taking the stairs protects your heart” more than doubled the number who chose stairs over the escalator at a suburban mall. If every shopper climbed the stairs on the way to the food court, Americans could lose several extra pounds … and a few unnecessary laws.