Low-Glycemic, Low-Carb Diets Allegedly Burn More Calories Than Low-Fat Regimes
A recent study analyzing the effects of three weight-loss maintenance diets has purportedly concluded that subjects who adhered to either a low-glycemic or very low-carbohydrate diet burned more calories than those on low-fat diets. Cara Ebbeling, et al., “Effects of Dietary Composition on Energy Expenditure During Weight-Loss Maintenance,” Journal of the American Medical Association, June 2012. According to a June 26, 2012, Boston Children’s Hospital press release, researchers analyzed data on total energy expenditure from 21 adult participants who first lost 10 to 15 percent of their body weight and then completed each of the following three diets in random order for four weeks at a time: (i) a low-fat diet comprising “60 percent of daily calories from carbohydrates, 20 percent from fat and 20 percent from protein”; (ii) a low-glycemic-index diet comprising “40 percent of daily calories from carbohydrates, 40 percent from fat and 20 percent from protein”; and (iii) a low-carbohydrate diet comprising “10 percent of daily calories from carbohydrates, 60 percent from fat and 30 percent from protein.”
The results evidently showed that the very low-carbohydrate diet produced “the greatest improvements in metabolism” but also increased participants’ C-reactive protein and cortisol levels, “which can lead to insulin resistance and cardiovascular disease.” By comparison the low-fat diet reportedly “caused the greatest decrease in energy expenditure, an unhealthy lipid pattern and insulin resistance,” whereas the low-glycemic-index diet appeared to have “qualitatively similar, although smaller, metabolic benefits to the very low-carbohydrate diet, possibly without the deleterious effects.”
“In addition to the benefits noted in this study, we believe that low-glycemic-index diets are easier to stick to on a day-to-day basis, compared to low-carb and low-fat diets, which many people find limiting,” said one of the study’s authors. “Unlike low-fat and very- low carbohydrate diets, a low-glycemic-index diet doesn’t eliminate entire classes of food, likely making it easier to follow and more sustainable.”
