Opponents of the administration’s “public health” plans shouldn’t just debate the government’s proper role in people’s health; they should also point out that its population-wide diet advice goes well beyond what science has established. “Some people in this field act more like zealots with a passion for a cause than scientists waiting for the evidence to support their conclusions,” complains California Polytechnic public-health economist Michael Marlow. As Marlow notes, America’s obesity rate was far lower back when nutrition was largely a parental responsibility, before government became widely involved in the diet-advice business.