Panel Urges Reducing Trans Fats in Diet

Americans consume too much of a form of fat that drives up blood levels of "bad" cholesterol and increases the risk of heart disease.

But because the substance is omnipresent in food, eliminating it from the national diet is next to impossible—and might have adverse health consequences if people unintentionally cut back on key nutrients.

How Much is Too Much?

That is the conclusion of an expert panel tasked by the US Food and Drug Administration (FDA) with evaluating so-called trans fatty acids. The FDA has been grappling with a proposed rule to set dietary guidelines for trans fats. But while the National Academy of Sciences (NAS) panel said Americans should cut back on their intake of the substance as much as possible, it could not recommend a safe upper limit.

The FDA in 1999 proposed a rule requiring food labels to carry information about trans fatty acid content. At the time, the agency suggested that manufacturers combine saturated fat and trans fatty acid content into a single unit, which would be listed as both grams and as a percentage of a recommended daily intake. It has never finalized that regulation.

Christine Lewis Taylor, an FDA official in charge of the new rule, said the NAS document "gives us the direction we need" to complete the regulation. But she said the agency has decided to break out trans fat into its own category.

Taylor said the final rule should appear within the next six to eight months. Information posted on the agency's Web site said the rule could ultimately prevent 6,300 to 12,800 cases of heart disease and 2,100 to 4,200 deaths a year.

Alice H. Lichtenstein, a Tufts University nutrition expert and a member of the NAS panel, said combining saturated and trans fats into a single line would have been an appropriate solution. "Since the message on how to treat them is the same, you want to provide as simple a message as possible, which is to decrease intake," she said. "I don't think the consumer is going to do anything differently if they were split and labeled on two lines."

The current food label intake guideline for saturated fats—like those found in red meat—is 20 grams a day, out of a total fat budget of 65 grams daily.

New Guidelines Expected Soon

Lichtenstein's group is now coming up with Dietary Reference Intakes for a variety of nutrients, including fats, fiber, carbohydrates, and protein. Those guidelines are expected by the end of the summer.

What Are Trans Fatty Acids?

Trans fatty acids are a form of unsaturated fat—meaning their molecular structure has free space for hydrogen atoms found naturally in dairy products and meat. Food makers create it when processing oils into margarine and shortening, so it shows up in fried and baked foods, too.

Once considered relatively benign, studies in the last decade have shown that eating trans fat leads to higher low-density lipoprotein (LDL), the "bad" cholesterol, and higher total cholesterol. It may also lower high-density lipoprotein (HDL), the "good" cholesterol, although the panel noted that the evidence here is not consistent.

Since high LDL and total cholesterol are linked to heart disease, scientists believe people who eat foods rich in trans fatty acids are more vulnerable to heart attacks, strokes, and other cardiovascular problems.

The panel reviewed a raft of earlier studies on trans fatty acids and health, concentrating on those dealing with the substances' effects on cholesterol and heart disease.

Dr. Walter Willett, a nutrition expert at the Harvard School of Public Health, said the message in the NAS report "could hardly be clearer," and that the FDA rule, when it arrives, will benefit consumers. "If they just put the specific amount of trans fat on the label it will give consumers information that will be very helpful to them."

A Warning About Food Labels

However, Willett cautioned that some manufacturers have started using the words "vegetable shortening" to disguise the presence of partially hydrogenated oils. "It makes it very hard" for people to know what they are eating, he said.

Regina Hildwine, senior director for food labeling and standards at the National Food Processors Association, a trade group in Washington, D.C., said the report contained few surprises.

Hildwine said her group's members have not opposed a trans fat item on package labeling. And she added that in the last decade many companies have taken steps to reduce the substances in their products, including certain baked goods and spreads.

The bulk of trans fat in food is produced by the partial "hydrogenation" of oils into solids. So until the new label appears, look out for this word on the foods you buy.

Always consult your physician for more information.