In a study published yesterday, 12 faculty members from the Harvard Medical School (HMS) and the School of Public Health (SPH) said that eating one egg per day does not increase one's risk of heart disease or stroke.

"There is this thought that eggs are bad for you because they're high in cholesterol, yet there's not good data indicating that eggs increase the risk of heart attack," said SPH Associate Professor of Epidemiology and Nutrition Eric B. Rimm, one of the study's authors.

Many popular diets recommend limiting the consumption of eggs, but these recommendations are often based on indirect evidence, according to SPH Professor of Epidemiology and Nutrition Meir J. Stampfer, another author of the study.

The logic behind these recommendations came from the belief that eating eggs, which are high in cholesterol, would automatically lead to higher levels of blood cholesterol.

The flaw in this belief, according to the study's authors, is that the main types of dietary cholesterol, saturated and trans fats, are not found in eggs. While eggs have both "bad" cholesterol and other less harmful kinds, there is not enough of any harmful cholesterol in one egg to pose a major health threat.

"What we found is contrary to common belief," Rimm said. "We found that there is no evidence of a link of [average] consumption, which we would define as one a day, and risk of heart attack or stroke among people who are free of disease."

Researchers say they hope that their research will help improve public awareness of how what people eat affects their health.

"I'm hoping that [the study] will shift people's attention from focusing too much on eggs," Stampfer said, "and instead focus on other changes in diet which would be more beneficial."

But not everybody can relax about egg consumption.

Diabetics and people with already-high cholesterol still have to worry about eggs, since they raise both the "good" fats--high-density lipids--and the more harmful low-density lipids.

"I don't think this is license to have two eggs, bacon, sausage and a fatty breakfast," said Rimm, who noted that the findings do not change current dietary recommendations for fruit, vegetable, grain and fat intake.

The ongoing study is based on two control groups, whose members answer questionnaires every two years. The Nurses' Health Study group, comprised of 80,082 women, was formed in 1976. The Health Professional Follow-up Study, comprised of 37,851 male health professionals, was formed 10 years later.

The female subjects began recording their egg intake in 1980, and the men in 1986. After some members of the group had heart attacks, the researchers could compare the incidence and absence of heart disease with the amount of egg consumption.

The study's first author is Dr. Frank B. Hu, research associate in the SPH's Department of Nutrition. Frederick Stare Professor of Epidemiology and Nutrition in the Faculty of Public Health and Professor of Medicine Walter C. Willett served as senior author.

Stempfer said that his diet has changed since the results were compiled.

"Even though I was skeptical [about eggs being unhealthy] going into it, it's nice to have the data to show," he said. "And after I saw the data I guess I started to eat a few more eggs now and then."