Low-Carb Diet Research and News

Success of Atkins diet is in the calories

Oct. 29, 2000

By Nanci Hellmich, USA TODAY

People on the Atkins diet slash their calories by more than 1,000 a day, which may partly explain why some report dramatic weight loss with the low-carbohydrate diet, a study says.

The research, which is being presented today in Long Beach, Calif., at the annual meeting of the North American Association for the Study of Obesity, is one of several new studies on the wildly popular diet.

The Atkins diet encourages people to eat bacon, pork, steak, butter, cheese, nuts and other high-fat, high-protein foods and to avoid carbohydrates, including pasta, breads, cereal, sweets, some starchy vegetables and many fruits.

Cardiologist Robert Atkins, who first published his diet in 1972, has said that his plan has "metabolic advantages" and that people can eat more calories on his program than they can with other diets and still lose weight. He says the reasons are not known yet.

In the new study, doctors at the Bassett Research Institute in Cooperstown, N.Y., had nine overweight men and nine overweight women — each at least 30 pounds over a healthy weight — keep track of what they ate for several days before beginning the Atkins diet. The doctors then gave them copies of Dr. Atkins' New Diet Revolution and some instruction.

Researchers analyzed the diet records and found:

• During the first, most restrictive phase of the Atkins program, dieters consumed 1,419 calories a day, compared with 2,481 calories a day before they began the diet. At the end of two weeks, they had lost a little more than 8 pounds on average.
• In the Atkins ongoing weight-loss phase, dieters ate an average of 1,500 calories a day and lost an additional 3 pounds in two weeks.
• Dieters in both phases of the Atkins diet severely cut back on carbohydrates (by more than 90%), but the actual amount of fat and protein they ate was pretty much the same while they were dieting as beforehand.

Allan Green, director of the institute, says the study demonstrates that people lost weight because they cut calories. "Weight loss is still calories in and calories out."

Bernard Miller, an internist at Bassett Healthcare and the lead author of the study, says some patients felt tired, and some were nauseated on the plan.

"A few of the study participants said they would continue the Atkins diet after the study was over, but the majority were eager to go back to their regular diet," Miller says.

"We're not recommending this diet to anyone," Green says. "We don't know what would happen if you followed it for years. What we found is it seems to work for short-term weight loss."

Two other studies are being presented at the meeting:

Researchers tracked 41 overweight people who followed the Atkins diet for six months and found that they lost an average of 10% of their initial body weight. Most lowered their cholesterol by 5%, but some increased their cholesterol.

Twenty subjects continued the program, and they had maintained their weight loss at the end of a year, says study director Eric Westman, an internist at the Durham (N.C.) Veterans Affairs Medical Center.

Researchers who compile the National Weight Control Registry analyzed the diets of 2,681 members who had maintained at least a 30-pound weight loss for a year or more. They found that less than 1% had followed a diet similar to the Atkins program. Most followed high-carbohydrate, low-fat diets, says James Hill, director for the Center for Human Nutrition at the University of Colorado Health Sciences Center in Denver.