Trans Fats Up Heart Disease Risk
Study Shows Tripled Risk for Heavy Users; Doctors Call for Ban
WebMD News Archive
Nov. 15, 2006 (Chicago) -- Trans fats have jumped out of the deep fryer into
a public grilling once again, with new research suggesting even small amounts
can harm the heart.
An analysis of data from the large Nurses' Health Study shows that women who
ate the most trans fats were more than three times as likely to develop heart disease as those who consumed the
The findings, presented here at the annual meeting of the American Heart
Association (AHA), support recommendations to avoid trans fat as much as
possible, says researcher Qi Sun, MD, of the Harvard School of Public
AHA President Ray Gibbons, MD, went further. The professor of medicine at
the Mayo Clinic in Rochester, Minn., says he supports a ban.
"There was no threshold below which they were safe," Sun says.
But "We saw a linear relationship: The more trans fats you consume, the
worse it is for your heart," he tells WebMD.
Trans Fats in Processed Foods
The report will no doubt please New York City Mayor Michael Bloomberg, who
has called for a ban on the fats in that city.
Once praised for making crunchy foods crunchier and creamy foods creamier,
trans fats are in fact one of the most dangerous forms of fat.
Engineered from liquid oils through a process known as hydrogenation, they
lurk in most processed foods -- including cookies, baked goods, popcorn,
margarines, shortenings, crackers, doughnuts, chips, frozen waffles, and french
fries. You can't get away from them.
Doctors have known for years that these fats can be damaging to the heart,
but the new study is one of the first to quantify just how harmful they are,
Also, the study was unique in that the researchers used trans fatty acid
levels in red blood cells as a marker of participants' trans fat intake. Past
studies used food questionnaires or food diaries, which depend upon people's
often poor recall, he says.
Just 1.3 Grams Harmful
The Nurses Health Study is one of the longest-running major women's health
investigations ever undertaken.
In this research, Sun and colleagues looked at the trans fat consumption of
166 study participants who developed heart disease between 1989 and 1995, and 327
women who did not.
The women were divided into four groups depending on their trans fat
Those in the highest quartile -- who consumed an average of 2.0 grams of
trans fats per 1,000 calories a day -- were at highest risk for heart
But even those eating just 1.3 grams per 1,000 calories per day were at
That's not much, when you consider that a typical serving of french fries
has about 5 grams of trans fats, a Danish has more than 3 grams, and even
microwave popcorn has 1.1 grams, Sun points out.
Eliminating such fats from your diet is a bit easier than in the past as the
FDA now requires all manufacturers to list the amount of artery-clogging trans
fats present in packaged foods.
But knowing how many were in that burrito you had for lunch is another
"We still don't know that any level of trans fats is OK," Gibbons
tells WebMD. "This study buttresses arguments to get rid of them."
Gibbons notes that in 2004, Denmark enacted legislation to eliminate
industrially produced trans fats from the food supply.
"While it took a lot of effort in the first few months, everyone seems
happy with their food now. And they're a whole lot healthier," Gibbons