The study followed two groups of dieters (148 people total) -- representing a cross-section of Americans and including a range of ages, races, incomes and health. Researchers tracked the two groups for a year as they attempted to lose weight. One group went with a low-carb diet, getting just 28 percent of their daily calories from carbohydrates. The other group went with the more traditional low-fat diet, getting 40 to 45 percent of their calories from carbs.
Each group ate roughly the same number of calories each day. When it was all said and done, the low-carb eaters had lost three times as much weight. They also demonstrated improved cholesterol levels and blood pressure numbers, suggesting their heart health benefit from a reduction in daily carb intake.
"Over the years, the message has always been to go low-fat," said lead author Lydia Bazzano, a nutritional researcher at Tulane University School of Public Health and Tropical Medicine. "Yet we found those on a low-carb diet had significantly greater decreases in estimated 10-year risk for heart disease after six and 12 months than the low-fat group."
"It's not a license to go back to the butter," added Bazzano, "but it does show that even high-fat diets -- if they are high in the right fats -- can be healthy and help you lose weight."