Two studies vindicate the Atkins diet -- but does the weight loss last?
Thursday, May 22nd 2003, 12:00 am
By: News On 6
A month after Dr. Robert C. Atkins' death, his much-ridiculed diet has received its most powerful scientific support yet: Two studies in one of medicine's most distinguished journals show it really does help people lose weight faster without raising their cholesterol.
The research, in Thursday's New England Journal of Medicine, found that people on the high-protein, high-fat, low-carbohydrate Atkins diet lose twice as much weight over six months as those on the standard low-fat diet recommended by most major health organizations.
However, one of the studies found that the Atkins dieters regain much of the weight by the end of one year.
Atkins, who died April 17 at age 72 after falling and hitting his head on an icy sidewalk, lived to see several shorter studies that found, to researchers' great surprise, that his diet is effective and healthy in the short run.
Although those reports have been presented at medical conferences, none until now has been published in a top-tier journal. And one of the studies in the journal lasted a year, making it the longest one yet.
"For the last 20 years that I've been helping people lose weight, I've been trashing the Atkins diet -- without any real data to rely on," said Dr. Michael Hamilton, an obesity researcher who was not part of either study. "Now we have some data to give us some guidance."
Now, he said, he would neither trash it nor endorse it. "I'm going to say I don't know. The evidence isn't in," he said.
One study ran six months and was conducted by the Veterans Affairs Department; the yearlong study was led by Gary D. Foster, who runs the weight-loss program at the University of Pennsylvania School of Medicine.
Atkins' diet books have sold 15 million copies since the first one was published in 1972. From the start, doctors branded the Atkins diet foolish and dangerous, warning that the large amounts of beef and fat would lead to sky-high cholesterol levels.
In both studies, the Atkins dieters generally had better levels of "good" cholesterol and triglycerides, or fats in the blood. There was no difference in "bad" cholesterol or blood pressure.
Dr. Frederick F. Samaha of the Philadelphia Veterans Affairs Medical Center, who led the VA study, said both studies indicate that people do lose more weight on Atkins, "but the difference is not great."
The 132 men and women in the VA study started out weighing an average of 286 pounds. After six months, those on the Atkins diet had lost an average of 12.8 pounds, those on the low-fat diet 4.2.
The other study involved 63 participants who weighed an average of 217 pounds at the start. After six months, the Atkins group lost 15.4 pounds, the group on the standard diet 7.
But at the end of a year, the Atkins dieters had regained about a third of the weight. Their net loss averaged 9.7 pounds. The low-fat dieters had regained about one-fifth of the weight, for a net loss of 5.5 pounds.
The year-end difference was not big enough to tell whether it was caused by the diets, Foster said.
About 40 percent of the patients dropped out of each study. And while supporters of the Atkins diet say it is easier to stick with, people on the Atkins regimen were just as likely to drop out as people on the standard diets.
The important finding, Foster said, is that the Atkins diet appears to be a healthy short-term way to lose weight. Nobody has studied it long enough to tell whether it is a healthy way to maintain that loss, he said.
Collette Heimowitz, director of education and research at Atkins Health and Medical Information Services, said people there were not surprised by the weight loss and improved cholesterol.
"But I'm thrilled that serious researchers are taking a hard look at the program, so that health care professionals and physicians would find comfort in offering Atkins as an alternative to the one-size-fits-all hypothesis of low-fat, low-calorie," she said.
The studies did not convince Kathleen Zelman, a spokeswoman for the American Dietetic Association.
"There's never been any denying that low-carbohydrate, high-protein diets such as Atkins do, absolutely, cause weight loss," she said. "But do they hold up over time and can you stay on them over time?"
From Foster's study, it does not look like it, she said.