By SALLY SQUIRES
Washington Post

A yearlong, head-to-head study of four widely used diets found that overweight women who followed the very low-carbohydrate Atkins Diet had no adverse health effects and lost slightly more weight than women on the other three.

The study by Stanford University researchers compared the Atkins approach with three others: the standard low-fat, reduced-calorie regimen long recommended by many physicians and weight-loss experts; the Zone, a reduced-carbohydrate approach developed by author Barry Sears; and the very low-fat, high-carbohydrate regimen created by physician Dean Ornish.

The latest findings add to a growing body of evidence that the very low-carbohydrate, high-protein Atkins diet doesn't cause the harmful heart and artery effects long feared.

Women who followed the Atkins plan had a significant drop in triglycerides, one of the unhealthful blood fats linked to a higher risk of heart disease. Their blood pressure also dropped the most of the four groups, a finding that the researchers think may relate to their slightly greater weight loss. Those in the Atkins group also experienced the largest increase in high-density lipoprotein (HDL), a protective type of cholesterol.

Most importantly, the Atkins group didn't develop the soaring levels of low-density lipoprotein (LDL) that some experts have feared might result from eating a diet rich in saturated fat and cholesterol found in fatty cuts of meat, butter and cream. High levels of LDL are a major risk factor for heart disease. The study found that while LDL rose slightly in the Atkins group, their blood levels didn't differ statistically from the other three groups.

No drastic weight loss
Because of its size, duration and the small number who dropped out, "this is the best study so far to compare popular diets," said Walter Willett, chair of the department of nutrition at the Harvard School of Public Health. The findings confirm, he said, that reducing carbohydrates, "especially those with refined starch and sugar like that found in the U.S. diet, has metabolic benefits." It also shows that replacing these carbohydrates with either fat or protein "can improve blood cholesterol fractions and blood pressure," he said.

As for weight loss, the goal that concerns dieters the most, none of the groups managed to shed the large numbers of pounds touted by weight-loss programs and television shows.

All the participants reported eating about 2,000 calories a day when the study began. All also reported having cut their intake � some by as much as 500 calories per day at two to six months � but then gradually added back many of those calories. But as researchers noted, if participants truly ate as little as they said, all the groups would have lost much more weight.

At first, the Atkins group lost weight faster. But as in previous studies, the pounds shed began to even out across the four groups. After a year, women in the Atkins group averaged a modest 10-pound loss compared with about 6 pounds for those in the three other groups.

Both the authors and other weight-loss experts were quick to note that the new findings didn't answer the question of what is the best way for most people to shed weight.

"This isn't a study testing how well you would do if you followed these diets to the letter," notes Christopher Gardner, assistant professor of medicine at the Stanford Prevention Research Center and lead author of the study, which appears in Thursday's Journal of the American Medical Association. "This is a study that shows what happens if you bought the book and tried to follow" the diets as most dieters do.