NEW ORLEANS - A Mediterranean-style diet high in olive oil and other "healthy" fats is just as good as the classic American Heart Association low-fat diet for the 8 million Americans who have suffered a heart attack and want to prevent a repeat, new research suggests.

People on either diet had one-third the risk of suffering another heart attack, a stroke, death or other heart problem compared with heart patients eating in the usual way, the study found. The results of the study were presented Sunday at an American College of Cardiology conference.

Doctors said it was one of the best tests of specific diets on heart health, especially because participants stuck to it and achieved the goals for various fats that researchers set. The participants also were similar in treatments and other factors so the effect of the diets could be isolated.

"Both diets are prudent choices" for people at high risk of heart disease, said Dr. Katherine Tuttle of Providence Medical Research Center and Sacred Heart Medical Center in Spokane, Wash. She led the study and presented the results at the conference.

Both the Heart Association and the Mediterranean diet are low in saturated fat (less than 7 percent of total calories) and cholesterol (less than 200 milligrams a day). The typical American's diet contains twice those levels or more, Tuttle said.

In the study, those on the American Heart diet were told to keep total fat intake to less than 30 percent of calories. The Mediterranean dieters were allowed to go up to 40 percent, with the extra coming from healthier monounsaturated and polyunsaturated fats and foods like olive oil, avocados and especially fish. It aimed for 20 to 25 percent of calories to come from these sources, and fish three to five times per week was recommended.

Researchers thought this diet would prove best, because of the heart-helpful omega-3 fatty acids in the fish.

They tested this hunch on 202 people who had suffered heart attacks in the previous six weeks. Fifty were put on the low-fat diet and 51 on the Mediterranean diet. Both groups received two individual diet counseling sessions in the first month and six group sessions over the next two years.

The other 101 served as a comparison group. "They got the usual advice in the hospital -- that was it," Tuttle said.

All were prescribed standard heart care drugs like aspirin, beta blockers and statins to lower cholesterol. Deaths, second heart attacks, strokes and heart-related hospitalizations were tracked.

After four years, 83 percent of those on the low-fat or Mediterranean diets had survived without such problems; only 53 percent of the others did. Cholesterol levels improved in both diet groups but not the comparison group.

There was no difference in risk between the low-fat and Mediterranean diet groups -- both did well.

Despite being allowed more fat, those on the Mediterranean diet found it tougher than the Heart Association one, possibly because they were mostly older people unaccustomed to eating so much fish, Tuttle said.

"We really had to work to get these people to use olive oil instead of margarine or butter," she said.

Dr. Steven Nissen, a Cleveland Clinic heart specialist and president of the College of Cardiology who had no role in the study, said the study gave an important choice to people who want to reduce their risk.

"It's refreshing and it's interest to hear a report on the impact of a specific kind of a diet," and to be able to recommend two that are effective, he said.