Are trans fatty acid healthy?

Train off the Track

Comparing the healthfulness of trans fatty acids (TFA) to other
types of fat is sort of like comparing cigarette smoking to nail
biting: they’re both bad habits, but one of them just might lead to
an early demise.

In a recent telephone survey of consumer attitudes about nutrition,
1,000 people called at random were asked which was healthier;
saturated fats or trans fatty acids. After two decades of media hype about low-fat diets, I wasn’t really surprised to see that 40 percent said trans fatty acids are healthier than saturated fats.

Even so, I would have thought by now that a much larger
percentage of the population might have gotten the news that an intake of trans fatty acids is only slightly healthier than your average rain wreck.

A little is a lot

Trans fats are created by the hydrogenation of vegetable oil; a
process that gives the oil a longer shelf life and makes it less
well, oily. These qualities also make hydrogenated vegetable oil an appealing choice for “quick service” restaurants and snack foods such as cookies, crackers, and chips. But many studies over the past decade have shown trans-fatty acids to be associated with artery damage and a high risk of heart disease.

And that’s only part of what makes TFA dangerous.

In a review article published in the American Journal of Clinical
Nutrition, nutritionists at the Harvard School of Public Health
wrote that trans fats inhibit the natural process by which alpha-
linolenic acid is converted into EPA and DHA, the omega-3 fatty
acids that are critical to so many facets of good health. And in a
study of more than 800 subjects conducted at Chicago’s Rush
University Medical Centre, seniors who had a high trans fat intake
were found to be twice as likely to suffer from Alzheimer’s disease
compared to those with the lowest intake.

But how high is a high intake?

Bruce Holub, a professor of nutritional sciences at Canada’s
University of Guelph, told the Toronto Globe and Mail that
ingesting a daily gram of trans fat over several years is enough to
significantly boost your risk of heart disease. And professor Holub
points out that as few as two crackers can contain an entire gram of TFA.

Go figure

Last year the FDA announced that by January 2006 all Nutrition
Facts panels must list trans fat content. But until then, there’s a
relatively simple way to figure out the TFA content of processed
foods.

First check the list of ingredients. If the product contains
hydrogenated oil or partially hydrogenated oil, that’s obviously
your first trans fat tip-off.

Next go to the Nutrition Facts panel where you’ll see grams of
“Total Fat” listed. Below that, the fats will be broken down into
saturated, monounsaturated, and polyunsaturated fats. If the “Total Fat” number is higher than the other three combined, the difference between the two totals equals the grams-per-serving of trans fat.

Some products, however, aren’t required to list monounsaturated
and polyunsaturated fats. In that case, if the grams of “Total Fat”
are higher than the grams of “Saturated Fat,” it’s time to go back to the list of ingredients. If “hydrogenated” appears high on the list of ingredients, you’re definitely getting some trans fat. If “hydrogenated” appears lower on the list, the trans fat content is probably low.

Pop test

Let’s take a look at a popular brand of “natural light” microwave popcorn. Total fat is 5 grams, saturated fat is one gram, and no other fats are listed. So with 4 fat grams unaccounted for, we check the ingredients and find only three items, in this order: popcorn, partially hydrogenated soybean oil, and salt. That’s a pretty good indication that you’re getting at least a gram or two of trans fat, and maybe even four.

But be sure to also check the serving size. This 3-ounce bag of popcorn claims to be 2.5 servings. So if you sit down and eat the whole bag, you might end up getting well over 4 grams of trans fat.

And because trans fat is present in so many food products, it’s easy to see how you could pick up a dozen or more grams every day without even trying.

Zip, nada, goose egg

In the e-Alert “The New Big Oil” (8/20/02) I told you about a 2002
report from a National Academy of Sciences panel that attempted
to set a safe intake level for trans-fatty acids. The report confirmed previous findings about the relationship of trans-fatty acids and the risk of heart disease, and concluded with this recommendation: “The only safe intake of trans-fat is zero.”

Every day we’re seeing more and more products claiming to be
“trans fat free.” Hopefully this will help that last 40 percent of
consumers catch on to the dangers of TFA. The result will be
better health for millions.

Sources:

“New Research Shows Shift in Opinion of Obesity Epidemic” 11th
Annual Consumer Attitudes about Nutrition, Pizza Marketing
Quarterly, 11/18/04, pmq.com
“Health Effects of Trans Fatty Acids” American Journal of
Clinical Nutrition, vol. 66, 1006S-1010S, ajcn.org
“Dangerous Fats Lurk in Seemingly Healthy Snacks” Paul Taylor,
Toronto Globe and Mail, 10/28/03, theglobeandmail.com
“Exposing Trans Fats” Lyrysa Smith, Albany Times Union,
10/28/03, timesunion.com
“NAS Panel: Only Safe Intake of Trans Fat is Zero” Center for
Science in the Public Interest, 7/10/02, cspinet.org