The fascination with low-carb versus low-fat diet continues; the latest news comes from a study in the Annals of Internal Medicine released today that found that people on both diets lost about the same amount of weight over two years. However, the low-carb group had an edge in raising HDL (good) cholesterol and lowering diastolic blood pressure
The study looked at 153 people who were randomly assigned to a low-carb diet, and 154 to a low-fat diet. The low-carb group limited carbohydrate intake to 20 grams per day for the first 12 weeks, then gradually increased fruits, vegetables, whole grains and dairy foods until they reached a desired weight. The low-fat group kept daily calories to 1,200 to 1,500, and fat to 30% of their diet.
Both groups also took part in a two-year behavioral program that focused on how to manage relapses, self-monitoring, and an emphasis on moderate physical activity.
Participants in both groups lost about 11% of their beginning weight at six months and a year after the study started, but gained some of the weight back. After two years, both groups had a 7% weight loss.
Although some health issues didn't vary between the groups, others did. The low-carb group had a substantially greater decrease in diastolic blood pressure (the bottom number that measures the heart at rest, in between heartbeats) than did the low-fat group at three and six months.The difference still remained after two years.
The low-carb group also had greater increases in HDL cholesterol than the low-fat group throughout the study. The study authors wrote that although macronutrients could have an effect on HDL levels, the mechanism isn't known and requires further research.
The authors concluded, "These long-term data suggest that a low-carbohydrate approach is a viable option for obesity treatment for obese adults."
-- Jeannine Stein