Multitudes use the the high-fat, low-carbohydrate Atkins diet, and now a carefully controlled study backs them up: A low intake of carbohydrates may actually take off more weight than a low fat diet and may be surprisingly better for cholesterol, too. For years, the Atkins formula of sparing carbohydrates and loading up on taboo fatty foods has been blasphemy to many in the health establishment, who view it as a formula for cardiovascular ruin.

But now, some of the same researchers who long scoffed at the diet are putting it to the test, and they say the results astonish them. Rather than making cholesterol soar, as they feared, the diet actually appears to improve it, and volunteers take off more weight. At least three formal studies of the Atkins diet have been presented at medical conferences during 2002, and all have reached similar conclusions.

The latest, conducted by Dr. Eric Westman of Duke University, was presented at the annual scientific meeting of the American Heart Association, long a stronghold of support for the traditional low fat approach.

In research financed by the Robert C. Atkins foundation in New York City, which promotes the Atkins diet, Westman studied 120 overweight volunteers. They were randomly assigned to the Atkins diet or the heart association's Step 1 diet, a widely used low fat approach. On the Atkins diet, people limited their carbohydratess to less than 20 grams a day, and 60% of their calories came from fat.

After six months, the people on the Atkins diet had lost 31 pounds, compared with 20 pounds on the AHA diet, and more people stuck with the Atkins regimen.

Total cholesterol fell slightly in both groups. However, those on the Atkins diet had an 11% increase in HDL, the good cholesterol, and a 49% drop in triglycerides. On the AHA diet, HDL was unchanged, and triglycerides dropped 22%. High triglycerides may raise the risk of heart disease.

While the volunteers' total amounts of LDL, the bad cholesterol, did not change much on either diet, there was evidence that it had shifted to a form that may be less likely to clog the arteries.

Healthy sources of fat should be chosen, keeping an eye on a sufficient intake of essential fatty acids and maintaining a proper ratio of Omega 6 to Omega 3 fatty acids.

Another diet that is high in fat, moderate in protein and low in carbs is the Rosedale diet. This diet accomplishes its goals by overcoming leptin resistance, reducing appetite and burning stored fat.