What's more, the patients did not see measurable increases in their blood-fat levels.

Although the researchers say further study is needed, they believe the results help substantiate the high-fat, low-carb diet made popular by the late Dr. Robert Atkins.

"Low and behold, we ended up with something very close to what Dr. Atkins had been saying for years," says Dr. James H. Hays, the endocrinologist and researcher who led the study at Christiana Care Health Services in Wilmington, Del.

Recent studies show the Atkins approach is effective for short-term weight loss. A key question is whether the diet will achieve results over a longer period of time while avoiding a harmful buildup of artery-clogging fat that could boost patients' risk for cardiovascular disease.

Hays is heartened by the diet's positive results with two other groups of patients who were tracked for longer periods of time. They included women with polycystic ovary syndrome, a hormonal condition, and people with reactive hypoglycemia, whose blood sugar drops after a meal.

Those with polycystic ovary syndrome lost 14.3 percent of their total body weight over 24 weeks. Reactive hypoglycemia patients dropped 19.9 percent of total body weight over a year. Neither group showed any significant change in blood-fat levels, Hays says.

In an editorial published in the same issue, Dr. Gerald Gau of the Mayo Clinic's Division of Cardiovascular Diseases expresses concern about the long-term cardiovascular risk of the diet. Still, he recommends researchers "keep an open mind regarding the role of the Atkins diet and continue to study its metabolic effects."

Hays' study focused on a relatively small sample of patients -- just 17 men and six women with atherosclerotic heart disease. All were obese and had been treated with cholesterol-lowering medications before entering the trial. Patients with diabetes were excluded.

Participants were asked to get half their daily calories from saturated fat, primarily red meat and cheese. Fresh fruit and non-starchy vegetables were allowed in restricted amounts, but starches were strictly forbidden.

The researchers don't know exactly how many calories patients consumed because participants were not required to precisely record their fruit and vegetable intake. The scientists estimate each meal contained at least 600 calories for a total daily intake of 1,800 calories. Almost all of the weight loss resulted from reduced caloric consumption, they believe.

Overall, the diet resulted in decreases in weight and body fat and participants kept blood-fat levels in check, the study found.

Not everyone will be persuaded by the results of the study, Hays says. "It's very small, it's very short and it's uncontrolled," he concedes.

Amy Joy Lanou, nutrition director at the Physicians Committee for Responsible Medicine, is among the skeptics. "I'd be very interested to see what happens with these individuals if the study was taken out over a year," she says.

The committee recently called on a U.S. advisory panel to warn the public about the dangers of high-protein, low-carb diets -- including the risk for cardiovascular disease -- in its next update of federal dietary guidelines.

Lanou advises people concerned about their weight to consider a diet proven to be safe and effective over a longer period of time. "We do know that choosing a plant-based diet will result in better health as well as weight loss," she says.