Even One Fatty Meal Affects Arteries
Effect of Meals High in Good or Bad Fat Immediately Apparent
in Arteries
By Jennifer Warner
WebMD Medical News
Reviewed By Louise Chang, MD
on Tuesday, August 08, 2006
Aug. 8, 2006 -- Eating just one fatty meal can have a major
impact on your arteries -- for worse or for better.
So says a new study that shows eating a meal high in
saturated fats, like a cheeseburger and fries, can reduce the
ability of the body's "good" HDL cholesterol to protect
against clogged arteries.
However, a single meal high in heart-healthy polyunsaturated
fats, like those found in sunflower and corn oil, can have
the opposite effect, helping protect the arteries from plaque
buildup.
"It's further evidence to support the need to aggressively
reduce the amount of saturated fat consumed in the diet,"
says researcher Stephen J. Nicholls, MBBS, PhD, PRACP, FACC,
a cardiologist at The Cleveland Clinic in Ohio.
"This study helps to explain the mechanisms by which
saturated fat supports the formation of plaques in the
arterial wall, and we know these plaques are the major cause
of heart attack and stroke," Nicholls says in a news release.
Saturated fats are mostly found in animal products like
butter, red meat, and lard. But they are also in some plant
products, such as coconut and palm oils.
Polyunsaturated fats are primarily plant-based and include
safflower, corn, and sunflower oils. They are usually liquid
at room temperature.
Fatty Meals Affect Arteries
In the small study, published in the Journal of the American
College of Cardiology, researchers looked at the effects on
14 healthy adults of eating a meal high in saturated fat or
polyunsaturated fat. Study participants had such a meal on
two separate occasions, one month apart.
Each meal consisted of a slice of carrot cake and milk shake
made with either saturated or polyunsaturated fat.
The meals were tailored to each participant and designed to
contain 1 gram of fat for every 2.2 pounds of body weight.
That amount of fat is equivalent to a double cheeseburger, a
large order of fries, and a large milk shake for a 150-pound
person.
The researchers found that three hours after eating the
saturated fat meal, the endothelium, or inner lining of blood
vessels, in study participants showed reduced ability to
expand and increase blood flow.
Six hours after the meal high in saturated fat, the "good"
HDL cholesterol's protective ability to prevent inflammation
was also impaired, the researchers found. Inflammation has
been linked to plaque buildup in the arteries.
In contrast, six hours after eating the meal high in
polyunsaturated fats, HDL's protective effects were enhanced.
The researchers found fewer inflammatory agents in the
participants' arteries than they did after the saturated fat
meal.
"We have a situation where consumption of a single meal
containing a high level of saturated fat is associated with …
impairment of a normal protective property of HDL," says
Nicholls. "In contrast, consumption of a meal high in
polyunsaturated fat results in HDL that is more protective."