Atkins diet: works only in short run

Atkins tops other diets in 4-way study

But maximum average weight loss after a year is only 10.4 pounds

By Chris Emery
Tribune Newspapers: Baltimore Sun

March 7, 2007

If you go on a low-carbohydrate diet to shed weight, you've probably made a good decision, according a new report by Stanford University researchers.

Just don't expect miracles.

In the largest head-to-head study of competing diets so far, low-carb plans such as the Atkins diet turned out to be safe and effective for losing weight and improving cardiovascular health -- at least in the short run.

In fact, women who aggressively restricted carbs lost nearly twice as much weight over six months as women on higher-carb diets, the Journal of the American Medical Association reported Wednesday.

The bad news: Even those on the Atkins plan, which outscored three competing diets, were down only 10.4 pounds after a year. And on every plan, by the end of the study, most dieters were slowly but surely regaining the weight they had lost.

"It shows that people will steadily go back to their old habits," said Dr. Lawrence Cheskin, director of the Johns Hopkins Weight Management Center.

Still, researchers welcomed the news that popular low-carb diets are safe and effective, if not a panacea.

Christopher Gardner, a professor of medicine at Stanford and the lead author on the study, also cautioned that the long-term safety of low-carb, high-protein diets is still in question.

"We don't know what a high-protein diet would do over 10 years," he said. "It could impair kidney function or leach calcium out of the bones. But we didn't look at that."

The study is the largest yet to explore the difference between popular diets. The researchers studied four diets representing a range of recommended carbohydrate consumption.

The Atkins diet calls for the fewest carbohydrates and lots of protein. At the other end of the carb spectrum was the Ornish diet, which focuses on cutting fat intake.

The study tracked the weight of 313 overweight or obese women for one year beginning in February 2003. The women were 25 to 50 and lived in the community surrounding Stanford's campus near Palo Alto, Calif.

Gardner said several factors might explain why the Atkins plan was somewhat more effective.

One, he said, is that Atkins calls for drinking lots of water, reducing the quantity of soft drinks and other sweetened beverages the women drank.

The diet also calls for protein-rich meals, which may have cut down on consumption of refined carbohydrates.