How about bad enough to diminish your body's
ability to defend itself against heart disease.
A recent study by researchers at the University
of Sydney in Australia
found just that reaction after 14 trial participants,
all healthy and between the ages of 18 and 40,
ate just one piece of high-fat carrot cake and
drank a milkshake.
That fat-laden feast compromised the ability
of the participants' arteries to expand to
increased blood flow, the researchers found. The
sudden boost in what's known as saturated
fat hampered the effects of so-called "good"
cholesterol, the high-density lipoprotein or HDL,
from doing its job -- to protect the inner lining
of the arteries from inflammatory agents that
promote the build-up of fatty plaques. It's
this plaque that, over time, clogs blood vessels
and causes heart disease.
"Saturated-fat meals might predispose to
inflammation of, and plaque buildup in, the vessels,"
said study leader Dr. David Celermajer, Scandrett
professor of cardiology at the Heart Research
Institute and the Department of Cardiology at
Royal Prince Alfred Hospital.
Celermajer's team had the volunteers eat
two meals, spaced one month apart. Each meal consisted
of a slice of carrot cake and a milkshake. But,
in one case the foods were made with saturated
fat, and in the other case the meal was made with
polyunsaturated safflower oil, a much healthier
The high-fat meal, which contained about 90 percent
saturated fat, had the equivalent of 68 grams
of fat. In contrast, the meal made with polyunsaturated
oil contained just 9 percent fat. The fat in the
high-fat meal was equivalent to a 150-pound man
or woman eating a double cheeseburger, a large
order of french fries, and drinking a large milkshake,
the researchers said.
Before and after each of the meals, the researchers
obtained blood samples from the participants so
they could evaluate whether the anti-inflammatory
properties of the so-called good HDL cholesterol
The anti-inflammatory properties did decrease
after the saturated fat meal, the researchers
said, but improved after the healthier polyunsaturated
The effects may be temporary, Celermajer said.
However, he's still concerned because the
effect may be occurring over and over, each time
a person eats a high-fat meal.
The study was published in the Journal of
the American College of Cardiology.
The message is clear, Celermajer said: It's
important to limit saturated fat intake as much
To do that, you've first got to know where
saturated fat lurks, said Jeannie Moloo, a Sacramento,
Calif., dietitian and a spokeswoman for the American
She suggests cutting down on meat, full-fat milk
and full-fat dairy products as a way to reduce
saturated fat. Those foods are all major sources
of saturated fat, Moloo said. So are processed
foods and snacks.
Switching to low-fat or non-fat dairy products
can minimize your total saturated fat intake,
Moloo said. Choosing foods wisely by reading the
Nutrition Facts label can help, too. For instance,
Moloo said, an ounce of regular cheddar cheese
contains 6 grams of saturated fat, while an ounce
of part-skim mozzarella contains less than half
that, or 2.9 grams.
Ice cream contains a lot of saturated
fat, Moloo tells her patients. For instance, she
said, one cup of vanilla soft-serve ice cream
has 13.5 grams of saturated fat. But some low-fat
ice cream bars contain just 1.5 grams of saturated
How much saturated fat per day is too much? Aim
for 10 percent or less of your daily calories
from saturated fat, Moloo suggested. The American
Heart Association sets the bar for saturated
fat at less than 7 percent of daily calories.
For instance, if your total calorie goal is 2,000
a day -- reasonable for moderately active adults
-- you should aim for no more than 20 grams of
saturated fat to keep your intake to 10 percent
or so. While few people will take the time to
add up their fat grams, doing so for a day or
two can give you an idea of how you are doing.