Source: DGNews  |  Posted 1 year ago

PHILADELPHIA -- August 4, 2010 -- The effectiveness of a low-carbohydrate diet versus a low-fat diet for weight loss have been frequently debated. According to a new study published in the Annals of Internal Medicine, both diets produce identical weight loss when coupled with comprehensive behaviour treatment, but a low-carbohydrate diet may help improve cardiovascular risk factors.

"Despite the conventional wisdom that a low-carbohydrate diet would actually make cardiovascular risk factors worse, it appears that across a lot of risk factors including blood pressure and lipid profiles, that a low-carbohydrate diet was associated with significant improvements," said lead author Gary Foster, PhD, Center for Obesity Research and Education, at Temple University, Philadelphia, Pennsylvania.

For the study, 307 patients were randomly assigned to either a low-carbohydrate diet (n = 153) or a low-fat diet (n = 154) with behaviour treatment. Weight at 2 years was the primary outcome, but other effects were measured throughout the study period.

At 3, 6, and 12 months, patients were evaluated for weight, serum lipid concentrations, blood pressure, urinary ketones, bone mineral density, and body composition.

The researchers found no differences in weight, body composition or bone mineral density between the 2 groups at any point during the study. However, dieters in the low-carbohydrate group had double the increase of good cholesterol levels versus the low-fat group (23% vs 11%, respectively) at 2 years.

"I think an important outcome from a study like this is to think about which diets fit best for which people," said Dr. Foster. "This study would suggest that perhaps for those with low HDL-cholesterol levels to begin with, that a low-carbohydrate approach to weigh loss may have some advantages."

At 2 years, both groups had lost a clinically significant amount of weight (about 7% of body weight), showing that successful weight loss can be achieved with either approach when coupled with a behavioural modification program.

"At the end of the day, behaviour interventions are key," said Dr. Foster "Dieters should be less concerned about what diet they follow, and more concerned with employing effective behavioural strategies, such as recording what they eat, logging their exercise, and limiting the triggers for overeating, like watching TV or eating in the car."

SOURCE: American College of Physicians