Low-Carb Beats Low-Fat for Weight Loss: Study
Still, experts agree there's no one-size-fits-all diet
People in both groups had counseling sessions with a dietitian: The low-fat group was told to get no more than 30 percent of their daily calories from fat, while the low-carbohydrate group was given a limit of 40 grams of carbohydrates per day. At the end of one year, the low-fat group averaged nearly 200 grams of carbohydrate daily compared to about 130 for the low-carb group, according to the study.
In the end, 82 percent of the low-fat group stuck with the diet for a full year. The same was true for 79 percent of the low-carbohydrate group.
By the one-year mark, people in the low-carbohydrate group had lost an average of almost 12 pounds. That compared with only four pounds for the low-fat group.
According to Hu, the findings do not mean low-carb is the "best" diet for weight loss. But, he said, "I think this means it's a good option."
Bazzano acknowledged, though, that many of the study participants didn't strictly follow their prescribed low-carbohydrate plan. "It was more moderate than that," she said. And she agreed that being "careful" about the amount and type of carbohydrates you eat is key -- as opposed to setting a rigid carbohydrate limit.
Angelone also pointed to another issue with the study: Sedentary study participants were discouraged from taking up exercise, to isolate the effects of the diet changes. But in real life, people would ideally change their diets and exercise.
"Muscles use carbohydrates as fuel," Angelone said. "It can be hard to exercise on a low-carb diet." Plus, she added, people on the low-fat diet, who were eating more carbohydrates, might have shed more weight if they'd been exercising.
Everyone agreed that there is no one-size-fits-all diet. When it comes to heart health, for example, there is strong evidence that the Mediterranean diet -- high in "good" carbohydrates and heart-healthy fats like olive oil -- is a smart option.
Ultimately, people need to make diet changes they can keep up for the long haul -- not just until they lose a certain amount of weight. The pounds will come back if you go back to your old ways, Angelone said.