(The New York Times News Service) -- Loading up on a high-protein diet such as the Atkins regimen will help people lose weight in the short term, because they generally won't want to eat as much of the rich food, medical professionals say.

Yet the question -- still unanswered, even after a highly-publicized study last week -- is whether people can keep the pounds off and their hearts healthy over the long haul.

During the six-month study, those who adhered to the Atkins high-protein/low-carbohydrate approach lost more weight and had better cholesterol response than those who followed a more traditional low-fat diet. After the study was presented last week at the American Heart Association's annual conference in Chicago, officials quickly released a statement saying that the research was too short-term and involved too few people to be significant.

"Any weight-loss program will lead to a reduction in cholesterol and triglycerides because you are losing weight," said Dr. Robert Bonow, the American Heart Association's president. "We don't have any long-term data that this is going to be effective continuing this."

The Atkins diet recommends eliminating sugars and fruits and strictly limiting the consumption of carbohydrates. Breads and pastas are barred, as well as starchy or high-sugar vegetables, including potatoes, corn and peas.

As the patient shifts from losing to maintaining weight, some fruits and some whole-grain carbohydrates can be added, but a daily carbohydrate threshold must be met, said Colette Heimowitz, director of education and research for New York-based Atkins Health and Medical Information Services.

Limiting carbohydrates means that people naturally start eating a higher percentage of protein, Heimowitz said. But that doesn't give them carte blanche to pig out.

"People twist this around. It's not about steak and bacon," she said. "It's about controlling carbohydrates.

"The body burns both fats or carbohydrates. Carbohydrates are the preferred fuel by the body, so if you restrict carbohydrates enough, the body will be forced to burn fat."

Bonow and other North Texas medical professionals say that the findings, and continued research into the Atkins diet and others, could help provide better insight into what is the best dietary approach.

Several said they discourage their patients from eating too much pasta and white bread, based on previous studies indicating that complex carbohydrates, such as whole-grain cereals and brown rice, are the preferred form. But Atkins followers, they say, risk losing out on the cancer- and stroke-prevention benefits of a diet richer in fruits and vegetables.

"Each has their own kernels of truth," said Dr. John Osborne, a Grapevine cardiologist. "A simple view of the world - all fat is bad and all carbohydrates are good - doesn't work. Unfortunately, the answer is going to be more subtle. It's going to be more complex."

The study, funded by the Dr. Robert C. Atkins Foundation and conducted by Duke University researchers, followed the food intake of 120 people for six months. After consuming roughly the same number of calories, the low-carbohydrate group averaged a greater weight loss than the low-fat group - 31 pounds versus 20 pounds.

Researchers found that patients were more likely to stick with the low-carbohydrate approach. Three-fourths maintained the regimen, compared with 57 percent of the low-fat participants.

No controlled study has followed the Atkins approach for longer than a year, Heimowitz said. An upcoming study funded by the National Institutes of Health is expected to follow its participants as long as five years, she said.

But even if larger, longer-term studies identify rising cholesterol and other problems with the Atkins approach, that won't dissuade people from trying it, said Dr. Margo Denke, a professor and nutritional researcher at University of Texas Southwestern Medical Center in Dallas.

"People want a diet that emphasizes what they can eat, not what they can't eat," she said. "I have lots of patients who swear by it - it's awful."

"We will see more gout, more hypertension and more high cholesterol."

A boomerang effect also is likely, Denke said. Cutting back on carbohydrates helps people lose body water, shed a few pounds and feel less bloated, she said.

"Then you cheat - you eat carbohydrates and you gain back the body water. This happens within a day or two."

Yet, Dr. Tim Coleridge has been intrigued by the diet for years, after testing it with more than 100 patients while he was stationed in Germany three decades ago. They lost an average of about 20 pounds and largely maintained it for a year, he said.

Some lost more than 100 pounds, he said: "I think the Atkins diet is good if you want to lose a large amount of weight."

Calories were strictly regulated, said Coleridge, now chief of the family medicine department at University of North Texas Health Science Center in Fort Worth. But by increasing the percentage of protein, the patients appeared to avoid the significant fluctuations in blood sugar that made them hungry more often and more prone to reaching for a candy bar, he said.

"The thing that made me cautious about pushing the Atkins diet was fear of the elevated cholesterol," Coleridge said. "To see that's not the case, it's somewhat of a surprise to me."

Copyright 2002 The New York Times News Service. All rights reserved.