Trans-Fat Trouble

You're probably eating more of them than you think. Here's why--and how to steer clear

by: Sally Wadyka

Before your next long run, you might fuel up by toasting a few frozen waffles. You might also pack an energy bar if you're going especially far. Along with all those energizing carbs, you figure you'll consume several grams of fat. But with all the calories you burn during your workout, there's nothing wrong with a few grams of fat, right? Not so fast. That depends on what kind of fat you're eating. There is good fat, and there is bad fat. And then there is something even worse--trans fat.

The unsaturated fats found in canola oil, nuts, avocadoes, and olive oil are good fats. They help lower LDL cholesterol (the so-called "bad" cholesterol) and raise HDL (the "good") cholesterol. Saturated fat--the kind in red meat, cakes, and some fried foods--is considered bad because it raises your overall cholesterol level and can lead to clogged arteries and heart attacks. "Think of fat like a sponge," says Lisa Dorfman, R.D., a sports nutritionist and spokesperson for the American Dietetic Association. "When fat molecules are completely soaked with hydrogen atoms, it's a saturated fat. When there are hydrogen atoms missing, it's an unsaturated fat."

The third and most harmful kind of fat is a man-made creation. "Back in the '70s, when everyone started realizing how bad saturated fat was, food manufacturers switched to using unsaturated fats, like vegetable oil," says Dorfman. "But to make them more stable, more solid, and easier to cook with, they had to add hydrogen back into them." The resulting hydrogenated oils are packed with trans fat, which not only increases bad, artery-clogging cholesterol, but also actually lowers levels of the heart-protecting good cholesterol. "The replacement was worse than the original," says Meir J. Stampfer, M.D., Ph.D., professor of epidemiology and nutrition at the Harvard School of Public Health. "Studies have shown that people who eat more trans fat have a higher risk for heart disease and diabetes."

Although small amounts of trans fat occur naturally in meat and dairy products, the man-made trans fat is much more prevalent. "It's very difficult to avoid them when eating any kind of packaged or processed foods," says Tara Geise, R.D., a spokesperson for the American Dietetic Association, and a nutritionist in private practice in Orlando, Florida. "And for now, manufacturers aren't required to list trans fat on the nutrition label."

That's about to change. Thanks in large part to the efforts of consumer-advocate groups such as the Center for Science in the Public Interest, the Food and Drug Administration will require all foods to list how much trans fat they contain by January 2006. And some food manufacturers--alert to consumer concern--have already started touting their products as having "no trans fat." But because manufacturers are not yet required to list trans fat, you have to pay close attention. "You need to read the list of ingredients and check for the words 'partially hydrogenated oils,'" says Geise.

Even then, you won't be able to tell exactly how much trans fat you're getting. But since ingredients are listed in order of the most to the least amount, simply try to avoid products that list partially hydrogenated oil as one of the first three ingredients. "If it's listed near the end, there's very little trans fat in the product," says Geise. She also recommends choosing foods that are low in overall fat. The lower a food's total fat content, the less trans fat it will contain. "For example, a chewy low-fat granola bar only has half a gram of trans fat," she says. Compare that to obviously fatty foods like a doughnut or a small serving of McDonald's french fries, both of which can pack up to five grams of trans fat, not to mention 10 grams of fat overall.

So how much trans fat is too much? When it comes to the man-made stuff, experts say you shouldn't have any at all. "It's the worst form of fat, and we need to get it out of our diets," says Stampfer. And no, you can't cheat because you're training for a marathon and "running it off." "People sometimes think that if they exercise and are fit and lean, they can eat whatever they want," says Stampfer. "That's not true. You can still be vulnerable to heart disease." So run--don't walk--away from those partially hydrogenated oils.

Trans-Fat Traps: Don't Fall In!
Chances are your grocery cart is loaded with trans fat. Here's how to fill it with healthier versions of these favorite runners' staples.

Energy bars
The ones that have a candy-like coating are most likely to contain trans fat. Read the ingredients label carefully and look for bars without the partially hydrogenated oils.

Hot Cocoa
Most mixes have trans fat. Make your own by heating skim milk in the microwave and adding some unsweetened cocoa and sugar.

Microwave Popcorn
The simple and healthy alternative is to air pop your own. Then flavor it with fat-free seasonings.

Muffins
Anything baked with shortening will contain trans fat. Ask bakeries or restaurants what they use. At home, bake with canola oil instead.

Pancake and Waffle Mixes
Most contain as much trans fat as cake mixes. Make your own mix or check the health food store for packaged versions without the hydrogenated oils.

Peanut Butter
Most processed peanut butters include partially hydrogenated oil. The good news is that these products typically contain less than two percent of the unhealthy oil, so by FDA guidelines they're considered "trans fat free." To go truly trans fat free, buy natural peanut or almond butter (the oil will separate).

Salad Dressing
Look for dressings with no hydrogenated oils, or better yet, make your own with olive oil and vinegar and your favorite herbs and spices.

Tortillas
The ones you find in the interior aisles of the store (which can stay fresh forever) probably contain trans fat. Instead, choose the ones in the refrigerated case (especially organic versions), which usually don't have trans fat in them