Study sees heart benefits in controversial Atkins diet
BY MARIAN UHLMAN
Knight Ridder Newspapers Posted on Wed, May. 21, 2003
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PHILADELPHIA - (KRT) - Score one for the Atkins Diet.
The popular and controversial low-carb diet helped people not only lose weight, but also reduce two risk factors associated with heart disease, University of Pennsylvania researchers said Wednesday.
When compared to a group of conventional dieters, people following the Atkins plan achieved significant increases in their "good" cholesterol and greater decreases in fats in the blood, known as triglycerides, according to the study published Thursday in the New England Journal of Medicine.
The improvements were similar to the benefits patients typically get from drugs, the authors said.
"Improvements of this magnitude are not usually seen with modest weight loss," said Gary Foster, the study's lead author and clinical director of Penn's Weight and Eating Disorders Program. "It is remarkable. . . . Low-carb approaches now become a viable option that we need to evaluate more fully, more systematically."
Foster said the differences are surprising because the two groups of dieters shed only modest amounts of weight after a year - 9.5 pounds for the Atkins dieters, compared to 5.4 pounds for the conventional dieters. The study started with 63 obese people who weighed an average of 216 pounds each.
After three months, Atkins dieters had lost an average of 14.7 pounds compared to 5.8 pounds in the conventional group. At six months, they had lost 15.2 pounds, versus 6.9 pounds.
Foster said it is too early to recommend the diet widely. Rather, it should be a launching point for further research.
In another article in Thursday's journal, a second group of University of Pennsylvania researchers at the Philadelphia VA Medical Center found that severely obese people also lost more weight, reduced their triglycerides and improved their ability to respond to insulin on a low-carbohydrate diet similar to Atkins. The six-month study involved 132 patients who weighed an average of 288 pounds. Those in the low-carb group lost about 13 pounds compared to about 4 pounds for the conventional, low-fat dieters.
Frederick F. Samaha, the lead author and chief of cardiology at the Philadelphia VA, said his group was most surprised with the benefits despite modest weight loss.
Because of relatively small size of both studies and high drop-out rate of participants (about 40 percent), the results should be interpreted cautiously, said Dr. Dena Bravata, lead author of a recent review of 107 low-carb diet studies.
Still, Bravata said, the new research contributes to a growing body of evidence that, in the short-term, low-carb diets "seem to be an effective means of weight loss, and they do not appear to have significant harmful side-effects."
Dr. George Blackburn, chief of the Center for the Study of Nutrition Medicine at Beth Israel Deaconess Medical Center in Boston, said the studies are "a first step."
They "start us on a new dietary approach with weight loss, provided that we can satisfy ourselves" that they won't lead to other health problems such as bone loss and loss of kidney function, he said.
While low-carbohydrate diets have been around since the 1860s, the late Robert C. Atkins helped to popularize them in recent years through his best-selling books. His books have sold about 14 million copies and about 25 million people have tried or are currently on the Atkins diet, said a spokeswoman for Atkins Health and Medical Information Services. Atkins died at 72 last month after slipping on ice and striking his head.
Low-carb diets have been criticized because they allow people to eat a limitless amount of fat and protein, but restrict the quantity of carbohydrates. A wealth of data over the past few decades indicate that "the consumption of high levels of saturated fat has adverse consequences on health," according to a perspective article in Thursday's journal.
"Let's not be focused on how quickly one loses weight," said Dr. Robert Eckel, who co-wrote the article and chairs the council on nutrition, physical activity and metabolism for the American Heart Association, in a telephone interview. "Be more concerned about the quality of the diet, and how that relates to sound nutrition and health," especially over time.
At one year, Foster's study is considered the longest head-to-head trial of the low-carb approach, and the first one to gather information at more than one research site. In addition to Penn, the other study collaborators were Washington University School of Medicine and the University of Colorado Health Sciences Center. The study was funded by the National Institutes of Health.
In the Foster study, those assigned to the low-carb diet were given Atkins' book and asked to follow the plan. The conventional group got a book directing them to follow a reduced-calorie plan of 60 percent carbohydrates, 25 percent fat and 15 percent protein, based on the U.S. Department of Agriculture's Food Guide Pyramid.
While the weight differences between groups diminished by 12 months, the "good" cholesterol levels - or HDL - had risen by 18 percent among Atkins dieters versus 3 percent among conventional dieters. The triglyceride levels declined in the Atkins group by 28 percent, compared to a 1-percent rise in the conventional group. Neither group showed any changes in the "bad" cholesterol at one year.
Foster, who now will head a study following patients for two years on the Atkins approach, said researchers need to find out if the low-carb approach helps patients maintain their weight loss better than conventional diets, and if the diet has any long-term effects on cardiovascular risk factors.