Trans-Fat-Free Food: What's the Truth?

The skinny on labels, calories, and what trans fat means to your diet.

By Kathleen Zelman, MPH, RD/LD
WebMD Weight Loss Clinic - Feature

Reviewed By Louise Chang, MD

We've made great progress since January 2006, when Congress required that trans fat content be listed on food labels. Food manufacturers and restaurants that used the unhealthy fats have scrambled to find alternatives so they can boast of their "trans-fat-free" foods. Bills to limit or ban trans fats in restaurants or school cafeterias have been introduced in at least 20 states.

Artery-clogging trans fats have been made out to be the bad guy in American diets -- and there's good reason for that. But the truth is that just because something is trans-fat-free, that doesn't necessarily mean it's healthy. Experts agree that using healthy fats, such as canola and olive oil, is better than using the artery-clogging trans or saturated fats. Yet all fats are loaded with calories -- and so need to be limited in our diet.

To make it even more confusing, labels boasting "zero trans fat" don't always mean a food is completely trans-fat-free. By law, such foods can contain small amounts of trans fats per serving. You'll still need to turn over the package and look at the list of ingredients and the nutrition facts panel.

So just what are trans fats? There are two types -- the naturally occurring type, found in small amounts in dairy and meat, and the artificial kind that results when liquid oils are hardened into "partially hydrogenated" fats. Natural trans fats are not the ones of concern, especially if you usually choose low-fat dairy and lean meats. The real worry in the American diet is the artificial trans fats, which are used extensively in fried foods, baked goods, cookies, icings, crackers, packaged snack foods, microwave popcorn, and some margarines.

These artificial trans fats started getting lots of attention after research showed that they could increase the risk for heart disease by increasing "bad" LDL cholesterol and decreasing "good" HDL cholesterol.

The American Heart Association (AHA) recommends limiting trans fat to less than 2 grams per day (a figure that includes the naturally occurring trans fats). The 2005 U.S. Dietary Guidelines simply recommend keeping trans-fats consumption as low as possible.

The Real Meaning of 'Zero Trans Fats'

In any grocery, you'll see many products boasting "zero trans fats." Yet this does not necessarily mean there is absolutely no trans fat in the product.

"Even though the label states "zero trans fats," one serving of the food can contain up to 0.5 grams of trans fat, according to the law, and still be labeled trans-fat-free," explains Elizabeth Ward, MS, RD.

The same guideline exists for saturated fats. Only when the food label states "no trans fats" does it really mean there are none.

The problem is that small amounts of these artery-clogging fats can add up quickly, especially if you eat several servings each day of foods that contain up to 0.5 grams per serving.

For example, popcorn can be an excellent source of fiber, is a whole grain, and can be low in calories. But if you eat several cups of microwave popcorn, the trans fat can really add up.

"Most people eat three cups at a sitting, which is three times the serving size and can have as much as 1.5 grams of trans fats," says Ward, author of The Pocket Idiot's Guide to the New Food Pyramids. "The same goes for trans-fat-free cookies that are easy to eat by the handful and add up quickly."

How to Find Trans Fats on Labels

The only way to be sure you're getting a truly trans-fat-free food is to check the list of ingredients on the label. Avoid products containing "partially hydrogenated fats or oils" (the main source of trans fats) or "shortening." Also keep in mind that some manufacturers are listing components of food ingredients separately so they can move trans fats lower on the list of ingredients.

Michael Jacobsen, executive director for the watchdog group Center for Science in the Public Interest, suggests looking beyond trans fats when you're reading labels.

"There is a frozen ice cream snack that claims zero trans fat, yet has 20 grams of saturated fat in one serving," he says. "So even though it has no trans fats, it contains a day's worth of saturated fat and is anything but healthy.

"Trans fats are the worst fats, even more so than saturated fats, but you must evaluate a food on the entire profile, including calories, total fat, saturated fat, vitamins, mineral, sodium, sugar, and fiber."

Trans Fat Substitutes



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