When it comes to losing weight, the current process for assessing calories is flawed. That's the conclusion of a panel of researchers who convened at the annual meeting of the American Association for the Advancement of Science to discuss how misleading calorie counts affect the human diet.
The method, known as the Atwater system, calculates the available energy in foods. But, as a story today in Wired points out, the system doesn't account for calories used to digest food, the possibility that bacteria in the digestive track may absorb some of the energy in foods, or the fact that foods in different forms, cooked vs. raw or ground vs. whole grain, are digested at different rates.
From the piece:
Why does all of this matter? Because we’re in the midst of an obesity epidemic and counting calories has been misleading, said David Ludwig, a pediatric endocrinologist at Children’s Hospital Boston and Harvard Medical School. How the body processes different foods in different ways matters. “The quality of calories is as important as the quantity of calories.” While others not on the panel welcome applying “the best science” to the problem of weight loss, they also provide a word of caution about getting too worried about precise calorie counts. “You can put a ton of effort into getting more accurate calorie counts,” says nutrition scientist Christopher Gardner of Stanford University in Palo Alto, California. “But why are you doing this? Will it make a real difference? If you want to lose weight, you still have to cut back on calories.” A few calories here and there may not matter to most people. But to the panel members, every little bit counts.