By
Lori Valigra, UPI Science News
CAMBRIDGE,
Mass., -- Having an egg a day is unlikely to increase the risk
of heart disease or stroke in healthy people, Harvard University
researchers say. Although this appears to contradict current American
Heart Association recommendations of no more than three to four
egg yolks per week, the Harvard researchers and other public health
experts still urge moderation in egg consumption.
The
study appears in Wednesday's issue of The Journal of the American
Medical Association. Dr. Frank Hu, an epidemiologist at the Harvard
School of Public Health who led the study, and his colleagues
tracked the egg consumption of more than 100,000 health professionals
who reported their eating habits. The study subjects were participants
in two large, long-term health studies: The Nurses' Health Study
and the Health Professionals Follow-Up Study. To avoid elevations
in blood cholesterol and to reduce risk of coronary heart disease,
the American Heart Association has advised the public to eat a
maximum of 300 milligrams per day of cholesterol and limit egg
consumption. Eggs contain about 213 milligrams of cholesterol
each. Most of the cholesterol is in the egg yolk.
Hu
said the study factors in eggs eaten plain and eaten as ingredients
in pancakes or other prepared foods. ''Moderate egg consumption
does not have a major effect on atherosclerosis (clogging of the
arteries) and can be part of a nutritious and healthy diet as
long as the overall diet is balanced,'' Hu said. Hu said the study
does not give all people a green light to eat more eggs. He said
people need to be cautious, especially diabetics and those with
high cholesterol. ''Not everyone in the world can go and eat one
egg per day,'' said Dr. William Krauss, head of molecular medicine
at the University of California at Berkeley and a member of the
American Heart Association's nutrition committee.
''The American Heart Association and other responsible public
health associations won't change their guidelines of 3-4 eggs
per week.'' Krauss added that most of the study participants were
health professionals who ate well anyway and tended to eat fewer
eggs. The authors speculated that one reason an egg a day doesn't
seem to impact heart disease or stroke risk is because there might
be nutrients in eggs that are beneficial in preventing coronary
heart disease.
However,
one group of people who seem to be at higher risk for coronary
heart disease if they eat too many eggs are people with diabetes.
The researchers said this might be because they have an abnormal
cholesterol transport mechanism. The average American ate 245
eggs per year in 1998, up from the 240 in 1997 but much lower
than the peak of 402 in 1945, according to the American Egg Board,
a Washington, D.C., group that represents egg producers.
The
American Egg Board welcomed the results of the study, saying that
eggs are a good source of protein and have 13 different vitamins
and minerals. ''The Harvard research is really the culmination
of a growing body of published data indicating that egg consumption
does not measurably raise blood cholesterol levels or have an
independent effect on heart disease risk,'' said Donald McNamara,
executive director of the American Egg Board's Egg Nutrition Center.
He
added, ''We hope the study will once and for all exonerate the
egg, so that people can enjoy its many nutrition benefits without
unwarranted fears of dietary cholesterol.'' But Hu said people
who eat eggs tend to eat them with other cholesterol-rich foods
such as sausage or bacon. Hu recommends not focusing on just one
cholesterol-rich food, but on eating a healthy and balanced diet,
reducing the intake of saturated fat (those that are solid at
room temperature such as butter) and trans fat (vegetable oil
that has been processed into a solid) and eating more grains,
fruits and vegetables.
