If the trend continues toward more fat and fewer vegetables and grains, Americans could suffer more heart disease, already the No. 1 killer in the country, they warned.

"It is pretty clear from marketing data ... that over the past two years there have been specific trends toward more fat intake in the diet. If that is true, that would then suggest that there are tough times ahead with regard to disease risk," said Dr. Randal Thomas of the Mayo Clinic in Rochester, Minnesota.

Several studies being presented at an American Heart Association meeting on nutrition and heart disease showed the same thing -- Americans eat too much overall, they eat too much fat, and they do not eat enough fruits, vegetables and high-fiber foods. Reporters were briefed on the San Francisco meeting in a telephone news conference.

Thomas and colleagues at the Mayo Clinic in Rochester, Minnesota, found that fat and especially cholesterol intake has gone up over the past five years among 1,200 area residents surveyed for the study.

In 1999, 70 percent of those surveyed were trying to eat less fat in their diets. The share fell to 65 percent in 2003. Daily cholesterol intake rose from 294 milligrams a day in 1999 to 331 in 2003.

Only 29 percent of the residents -- whom Thomas says are representative of the U.S. public -- met government recommendations of getting no more than 30 percent of calories from fat.

"Reasons for this trend are unclear but may include the aggressive marketing of dietary plans that recommend the liberal use of saturated fat and cholesterol in the diet," Thomas said in a report to the meeting.

FAT-RICH DIETS

Such fat-rich plans are led by the Atkins diet, which recommends overloading on protein and fat to cause a metabolic condition called ketosis, in which the body sheds water.

While some of these diets have been shown over the short term to help some people lose weight and to lower cholesterol, the Heart Association says there are no long-term studies and it does not recommend the diets.

On the other hand, greater intake of fat and cholesterol is known to worsen heart disease, Thomas said.

"What this (study) shows is some troubling trends," he told reporters in a telephone briefing.

"I think any diet that recommends increasing the amount of saturated fat poses a risk. There may be good things about the diet ... but any diet that recommends increases in saturated fat could be increasing the risk in the population."

And they may not help people lose weight, suggested a study by Linda van Horn of Northwestern University in Chicago and colleagues.

The study assessed more than 4,000 people in the United States, Britain, Japan and China, asking them to write down everything they had eaten over two 24-hour periods.

"Lo and behold, what we did find is that without exception, a high complex-carbohydrate, high-fiber, high vegetable-protein diet was associated with low body-mass index (the standard measure of healthy weight)," Van Horn said.

The more animal protein a person ate, the higher his or her weight, she said.

Dr. Robert Eckel of the University of Colorado, the Heart Association's spokesman on nutrition, said people should aim to eat plenty of fruits, vegetables and high-fiber grain foods, reduce fat consumption, and exercise.

"There are no good foods and bad foods. It is the overall diet that we are interested in," he said.

Source: Yahoo News: Reuters Health.