The low-carbohydrate diet may offer fast results, but maintaining those results over the long term is more difficult, according to the research.
The study has been published in the Annals of Internal Medicine. In the study, 132 obese people consumed either a low-fat diet with controlled kilojoules and less than 30% of daily kilojoules from fat, or a low-carb diet with less than 30 grams of fat per day. They followed the diet for 12 months.
"Although participants in the low-carbohydrate group lost more weight at 12 months, they regained more weight during the next 24 months," writes researcher Marion L. Vetter, MD, RD of the Hospital of the University of Pennsylvania and colleagues in the Annals of Internal Medicine. "In contrast, participants in the low-fat group maintained their weight loss."
After 6 months, the low-carb participants had lost the most weight, but after one year there was no significant difference between the two groups in terms of weight loss. What was most interesting, however, was that after three years (two years after the diets began), the people in the low-fat diet group had maintained double the amount of lost weight as compared to the low-carbohydrate diet group.
Both diets apparently offer weight loss results, but in the long run low-fat seems to win out. "The differences in weight regain between the two groups probably reflects initial weight loss," write the researchers. "Participants who lost more weight during the first 12 months tended to regain more weight by month 36."
