June 27, 2012
The study, funded by the National Institutes of Health, was designed to see if changing the type of diet people consumed helped with weight maintenance because dieters often regain lost weight.
So scientists had 21 obese participants, ages 18 to 40, lose 10% to 15% of their initial body weight (about 30 pounds). After their weight had stabilized, each participant followed one of three different diets for four weeks. Participants were fed food that was prepared for them by diet experts. The dieters were admitted to the hospital four times for medical and metabolic testing. . . .
Findings, published in this week’s Journal of the American Medical Association: Participants burned about 300 calories more a day on a low-carb diet than they did on a low-fat diet. “That’s the amount you’d burn off in an hour of moderate intensity physical activity without lifting a finger,” says senior author David Ludwig, director of the New Balance Foundation Obesity Prevention Center at Boston Children’s Hospital.
“Participants burned 150 calories more on the low-glycemic index diet than the low-fat diet. That’s about an hour of light physical activity,” he says.
The reason for the low-carb advantage is unclear, he says.
“We think the low-carb and low-glycemic index diets, by not causing the surge and crash in blood sugar, don’t trigger the starvation response. When the body thinks it’s starving, it turns down metabolism to conserve energy,” he says.
More research is needed, but it’s a mark in favor of Gary Taubes’ approach.