Plain sweet potatoes or pumpkin pie, turkey or Tofurkey, a calorie is still a calorie. At least, that’s what dieters have been told for the past half-century. Now, experts don’t agree
“By and large, we’ve been taking an accounting approach to weight loss,” says Dr. David Ludwig, a professor of nutrition at the Harvard School of Public Health. By that he means, health scientists have traditionally focused on the number of calories coming in versus the number of calories going out. But there are a lot of problems with that approach, he says. For one thing, it’s really tough to accurately keep track of your daily calorie intake. “Being off by just 100 calories a day could add up to a hundred pounds over a lifetime,” he says.