Trans Fatty Acids: The Heart of the Matter
Today's Dietitian
By Kate Jackson
Vol. 6 No. 2 p. 36

Do trans fatty acids (TFAs)—the latest household buzzwords in nutrition—contribute to cardiovascular disease?

According to leading nutrition experts, they do indeed. Is their role in the development of heart disease significant enough to justify their inclusion on nutrition labels? Is the link to poor heart health compelling enough to mandate a change in the public’s dietary habits? Do they rival saturated fats as threats to cardiovascular health? The answers to those questions vary depending on who you ask.

At one end of the opinion spectrum is Elizabeth Whelan, ScD, MPH, an epidemiologist who heads the American Council on Science and Health (ACSH), which describes itself as a consortium of more than 350 scientists and physicians dedicated to consumer education on public health issues. It describes its mission as helping the public distinguish between “real health risks and hypothetical or trivial health scares.” Whelan suggests that the dire warnings about TFAs are heavy on hyperbole.

At the other end of the argument is the notoriously vigilant D.C. watchdog group the Center for Science in the Public Interest (CSPI), which has petitioned the FDA to mandate the labeling of foods with TFA content for 10 years. The CSPI, the organization that’s made Mexican and Chinese food guilty pleasures and has renamed fettucine alfredo “heart attack on a plate,” views TFAs as a significant and hidden health threat to American consumers.

What’s at the heart of this contentiousness? Although they may be naturally present in foods such as beef and dairy products, TFAs, or unsaturated fatty acids, more commonly result from a manufacturing technique that essentially whips liquid fats such as vegetable oil into solid fats. These “partially hydrogenated oils,” which lend texture and density to foods, are present in large quantities in spreads such as margarine and shortening, packaged foods such as cake mixes, some soups, deep-fried foods (including many fast foods), many frozen foods, commercially baked products such as donuts, potato chips, crackers, cereals, energy bars, cookies, candy, nondairy creamers, dips, gravy mixes, and salad dressings.

Studies have linked diets high in TFAs to an increased risk of cardiovascular disease. Some suggest that the risk is similar to that of those posed by saturated fats, while others indicate that TFAs may pose an even greater hazard. Moreover, consumption of TFAs has been implicated in the development of type 2 diabetes and cancer. A recent study has also suggested that it may play a role in increasing the risk of Alzheimer’s disease.

As researchers uncovered a connection between intake of TFAs and an increased ratio of low-density lipoproteins (LDLs) to high-density lipoproteins (HDLs), the media have generally portrayed TFAs as health blasters—a dietary hazard equal to or greater than that posed by cholesterol and saturated fats. Many concerned consumers have begun to scrutinize their diets and drastically reduce or attempt to eliminate TFAs. But, they have had little hope of determining how much trans fat is lurking in the foods they eat. Until now.

This summer, the FDA announced its decision to require food manufacturers to include information about TFAs on their products’ nutrition labeling along with information already listed about total fat content, as well as percentages of saturated, monounsaturated, and polyunsaturated fats.

While the FDA’s ruling will help consumers know how many grams of TFAs are in their food, it won’t help them know how much is too much. Other lipids on food labels are listed not only in terms of the number of grams of fat they contain, but also as a percentage of one’s Recommended Daily Intake of that fat. Unlike the food label listings pertaining to other fats, those for TFAs will include no “daily value.”

The FDA’s ruling relied heavily on reports from the Institute of Medicine (IOM), which did not conclude safe limits of TFAs. The IOM report acknowledged that TFAs are so widespread in foods that eliminating them from one’s diet would be nearly impossible and to attempt to do so could eliminate certain foods to the extent that it would pose the risk of nutritional deficiency.

Nevertheless, the institute’s message was clear: Avoid consumption of TFAs. As a result, the new food labels will carry a footnote indicating that “intake of trans fats should be as low as possible.”

While this new rule won’t require food makers to list the quantities of TFAs in their products until January 2006, it certainly has food manufacturers scrambling to reduce the amount of TFAs in their products contain. Expect to see labeling and advertising that touts a product’s lack of TFAs. Furthermore, it has created widespread media attention, most of which has portrayed TFAs as a serious health hazard.

In light of the media’s renewed interest, and while the CSPI and the American Dietetic Association (ADA) have praised the FDA’s action in general, Whelan questions the government’s basis for requiring labeling of TFAs and asserts that the consequence of labeling will be little or nothing more than an unnecessary increase in costs as food manufacturers pass along the bill for labeling.

Whelan responded to a request for comment by referring Today’s Dietitian to the ACSH’s Web site, which contains an article titled “Dietary Demons” that outlines her opposition to labeling and her assertion that the entire issue of TFAs has been wildly overblown by the media. She charges that the press’s response to the FDA’s action was out of proportion, biased, and lacking in scientific substance. She takes issue with the notion that TFAs are a leading cause of heart disease and should be avoided.

While acknowledging that TFAs raise blood cholesterol and influence the levels of HDLs and LDLs, Whelan suggests that other factors, such as genetics and cigarette smoking, are more pertinent and that medication may be more effective than dietary changes in reducing cholesterol levels and thus preventing coronary heart disease.

Ruth Kava, PhD, RD, director of nutrition at the ACSH, agrees. “Yes, I think TFAs have been overhyped as being something that’s terribly dangerous. We’ve had trans fats in our diets for a long time. I mean, they may not have been in fast foods from the word go, but people have used Crisco shortening for decades, and that’s nothing if it’s not hydrogenated fat. So it’s there, and it’s been there.” Kava acknowledges that the levels of TFAs that are consumed may have increased but expresses the belief that rates of heart disease have been getting better, which she concludes “is probably due to people quitting smoking.”

Like Whelan, Kava feels the media, along with activist groups, are largely responsible for stirring the pot. “Any time you get all this media attention, and there are a few activist groups like CSPI that tend to hyperbolize to a certain extent, I think they exaggerate the risks,” Kava says.

About the CSPI, she observes that “their sound bytes are very earcatching—heart attack on a plate or artery-clogging fat—those phrases people can easily remember. Their point, I think, is to get people to pay attention to some of these issues, but along the way, I think that they exaggerate in order to get people’s attention.” This exaggeration, she suggests, takes people’s attention away from an emphasis on a healthy diet and focuses them on a dangerous food.

Not only does Whelan minimize the hazards, but she reminds readers of the benefits of TFAs: They prolong the shelf life of foods, help products retain their flavor, and are useful for frying foods. Finally, she maintains that the benefits of “labeling and phasing out” trans fats are unclear. “The government estimates that perhaps 250 to 500 coronary heart disease deaths [out of the total 500,000 that occur annually in the United States] will be prevented. But, those numbers are purely hypothetical,” she says, adding that “the real number of lives saved might be zero.”

In response, David Schardt, senior nutritionist, CSPI, suggests that because Whelan is inclined to defend the processed food industry, she downplays the significance of TFAs. “Yes,” he says, “trans fat is one of many factors influencing the risk of heart disease. But, it’s a potent one, strongly affecting one of the most important risk factors by raising blood levels of the LDLs. True, the role of trans fat is not as well-studied as cholesterol levels, but study after study has shown that we should avoid this processed fat.”

Schardt says that Whelan’s belief that Americans will not pay due attention to the hazards of smoking, high blood pressure, and obesity and focus instead on the threat of trans fats underestimates the intelligence of U.S. consumers. “There is no evidence that this is happening or would happen,” he says. “No responsible health organization has suggested that warnings about smoking, hypertension, or obesity should be replaced by warnings about trans fat.”

He also takes issue with Whelan’s assessment of TFAs’ benefits and the cost of adding TFAs to nutrition labels. The benefit of TFAs, Schardt says, are to produce fatty foods more cheaply, which increases obesity and thus contributes to cardiovascular disease. “Whelan worries that low-income Americans will have to pay a greater portion of their disposable income for foods made without trans fat,” he says. “That shows little faith in the ingenuity of American food scientists, who are working on healthier substitutes for trans fat. Of far greater threat to the pocketbooks and health of low-income Americans is the abundance of heavily advertised high-calorie foods, including many with relatively high levels of trans fat. If consumers were to eat fewer of these foods, they would likely save money on healthcare costs in the future.”

It may not be surprising that the CSPI, which many believe overstates nutritional threats, takes issue with Whelan’s statements. But, the ADA is puzzled by her position as well. ADA spokesperson Cindy Moore admits to surprise at being in more or less complete agreement with the CSPI and confused by Whelan’s assertions that the FDA acted without solid scientific input. “The Institute of Medicine’s National Academy of Sciences’ report came out in 2002, and the individuals who were on that commission were all scientists,” she says.

“What came directly out of the report was the recommendation that trans fatty acid consumption should be as low as possible while maintaining a nutritionally adequate diet. The report also concluded that TFAs behave like saturated fatty acids and raise LDL cholesterol.”

Moore explains that there have been many human-feeding studies and epidemiological studies that do show a positive association between the intake of TFAs and the incidence of coronary heart disease. These findings are reported on the FDA Web site. “To me, there is an ample amount of evidence that supports the recommendations for Americans to try to consume less foods with TFAs,” she says.

Moore also notes that the media take a bad rap for their coverage of the issue. “I thought that the media covered the topic appropriately.”

Moore takes exception with Whelan’s assertion that diet is less important than medication in controlling cholesterol. “The National Cholesterol Education Program guidelines advocate diet as the first targeting point to help lower cholesterol, and the American Heart Association guidelines that came out in 2002 advocate diet modifications to reduce the risk of coronary heart disease,” she explains.

Moore suggests that the bottom line for consumers is to eat foods that are going to be wholesome and contribute a variety of nutrients. She recommends following the U.S. Department of Agriculture Food Guide Pyramid, which suggests eating a variety of foods, including fruits, vegetables, whole grains, low-fat sources of calcium, and lean sources of protein. By following these guidelines, she says, “Individuals are going to reduce their intake of TFAs, saturated fat, and cholesterol.”

— Kate Jackson is a staff writer for Today’s Dietitian.

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