Atkins tops other diets in study
Keeping weight off remains a problem
CHICAGO -- The low-carbohydrate, high-fat Atkins diet gets high marks in one of the biggest, longest head-to-head studies of popular weight-loss plans, beating the Zone, the Ornish diet, even US guidelines.
Even so, critics say the results show how hard it is to lose weight and keep it off.
Overweight women on the Atkins plan lost more weight over a year than those on the low-carb Zone diet.
And they had slightly better blood pressure and cholesterol readings than those on the Zone; the very low-fat, high-carb Ornish diet, and a low-fat, high-carb diet similar to US government guidelines.
Stanford University researcher Christopher Gardner, the lead author of the study, said the results indicate that the Atkins program may be more healthful than critics contend.
But the study isn't a fair comparison because by the end, few women were following any of the diets very strictly, critics argue.
The study "had a good concept and incredibly pathetic execution," said Zone diet creator Barry Sears.
"It's a lot easier to follow a diet that tells you to eat bacon and Brie than to eat predominantly fruits and vegetables," said Dr. Dean Ornish, creator of the Ornish diet.
Atkins followers had lost about 10 pounds on average at 12 months, compared with 3.5 pounds for the Zone dieters.
Women on the Ornish diet lost almost 5 pounds on average and those on the national guidelines plan lost almost 6 pounds. Scientifically, those 12-month results weren't different enough from the Atkins weight loss to rule out the possibility that the differences occurred by chance.
The dieters lost the most weight early on, including 13 pounds on average for the Atkins group at six months -- nearly double the closest competitor, the national guidelines diet. After that, most began regaining weight, a trend most noticeable in the women on the Atkins diet.
With an average starting weight of about 189 pounds, even losing 13 pounds meant many women remained overweight.
"There's not a ton of weight loss here," Gardner acknowledged. Atkins "isn't the solution for the obesity problem," he said.
The study involved 311 women averaging about 40 years old and was designed to measure the effectiveness of using a diet book to lose weight.
Women were randomly assigned to read one of four diet books. They attended weekly classes for eight weeks where diet questions were addressed, but then were mostly on their own for the next 10 months.
At the end, Atkins dieters had slightly higher levels of HDL cholesterol and slightly lower blood pressure than those on the other three diets. Gardner said differences in weight loss probably contributed to those results.
Ornish and others argued that the study doesn't answer a big question about the Atkins diet -- whether eating all that fatty food long-term leads to health problems.
The study appears in today's Journal of the American Medical Association.
The authors said it's uncertain whether the results would apply to men or older women since none were studied.
The study "shows that nothing works very well," said Yale University food policy researcher Kelly Brownell. His book promoting diet and lifestyle changes similar to national guidelines was used in the study.
"To me, it just screams out for the need to prevent obesity," Brownell said.
The results echo a Harvard study published last year involving thousands of women, which also suggested that a low-carb, high-fat diet might be more heart-healthy than previously thought, although it relied on women's memories of what they had eaten over two decades.
Also, those who ate fat and carbs from vegetables rather than animal sources had lower heart disease risks in the Harvard study.
Dr. David Katz of the Yale Prevention Research Center and author of several weight control books, said the new study presents little new information and called it "much ado about nothing."
Nurse Jackie Eberstein, whose consulting company promotes the Atkins diet, said the results are not surprising. Protein makes people feel less hungry and fat helps them feel more full, which makes weight loss easier on Atkins, she said.
The study was funded by grants from the National Institutes of Health and from the Community Foundation of Southeastern Michigan.