April 24, 2009

You follow healthy eating habits and you decide to start your day with a nutritious bowl of General Mills Basic 4 cereal. Here's the problem:

A serving (55 grams, or about 1 cup) contains 200 calories, just 3 grams of total fats and grams of saturated fat.

But before you open the box, think about this: The label doesn't say so, but of the 3 grams of total fats per serving, 1 gram is trans fat, a particularly insidious type of artery-clogging fat. "Trans fats often double the trouble that foods cause to your heart," says Margo Wootan, Sc.D., nutrition policy director of the nonprofit Center for Science in the Public Interest (CSPI) in Washington, D.C., which has spent more than a decade lobbying the U.S. government for revised food labels that make clear to consumers the quantities of trans fats there are in food. "Some [foods] have as much trans fat as saturated fats."

Starting in January 2006, CSPI will get its wish. That's when the U.S. Food and Drug Administration (FDA) will require food labels to include trans-fat information. Then the public is likely to begin to fully grasp what consumer health advocates have known for years: There's a dangerous amount of trans fats hidden in many of our favorite prepared and processed foods.

Discover more about the dangers of trans fat, including how much is too much.

[header = Healthy eating habits: Trans fats can derail the best of them. Find out how.]

Trans fats can derail healthy eating habits. How much is too much?

Hidden trans fats wouldn't be such a big deal, nutrition experts say, if they weren't so damaging to your cardiovascular system. Like saturated fats, trans fats increase LDL cholesterol (the "bad" kind), escalating one's risk of stroke and heart attack. But trans fats may do even more damage: Some research suggests that they also lower levels of HDL cholesterol, the type that helps keep arteries clean.

"They essentially stick in your arteries more than other types of fat," says San Francisco Chronicle food writer Kim Severson, co-author of The Trans Fat Solution (Ten Speed Press, 2003), a guide to shopping and cooking without trans fats. Several studies, including the ongoing Nurses' Health Study conducted by the Harvard School of Public Health, have found strong evidence that trans-fat consumption substantially increases the risk of coronary heart disease. For example, the Nurses' Health Study noted that replacing just 2 percent of calories from trans fats with calories from unsaturated fats was associated with an astonishing 53 percent lower risk of the disease.

So how much trans fat is too much? What amount increases heart attack risk?

That's unknown. Even small increases in trans-fat consumption appear to elevate heart-disease risk, and there is no known safe limit. To date, the FDA has not issued a recommended "daily value" for trans fats, as it has for other nutrients. For its part, the agency simply recommends that trans-fat consumption be kept "as low as possible." That's why it's important to pay attention to even a small amount of trans fat. "Two grams here, 2 grams there can add up," Wootan notes.

According to FDA regulations, once trans fats do appear on labels, manufacturers will be able to round down their trans-fat totals if products have less than .5 gram. So foods with less than .5 gram per serving will be able to claim they are trans-fat-free.

The dangers of trans fat: Have they always existed?

[header = Dangers of trans fat: has this always hurt healthy eating habits? Or is it new?]

Have the dangers of trans fat always been around?

Although trans fats are found in small amounts naturally (primarily in some animal-based foods), almost all of what we get in our daily diets are manufactured. They're created when food makers add hydrogen to vegetable oil, a process called hydrogenation, which turns liquid oils into stable, long-lasting solids, such as shortening and many stick margarines. If you see "partially hydrogenated vegetable oil" on an ingredient list, you know the food contains trans fats. The food industry loves these fats: They're a cheap, effective way to make crackers crunchy, french fries crispy, cookie fillings creamy and frozen foods more flavorful. They also extend these products' shelf life.

But it's not just fried foods, processed baked goods and bread spreads that harbor trans fats. Laboratory testing by CSPI and other consumer organizations has also detected the fats in places you might not expect: Breakfast cereals, microwave popcorn, frozen waffles, packaged pudding snacks -- all contain partially hydrogenated oils, albeit in smaller amounts than a bucket of fried chicken. Even lowfat foods such as Kellogg's Low Fat Granola aren't trans-fat-free. "It's truly a stealth fat -- it's everywhere," Severson says, noting that some seemingly healthful foods like peanut butter, breakfast bars, flour tortillas, bean dips and even baby foods contain trans fats.

Limit your intake of trans fat to boost healthy eating habits.

[header = Recognize the dangers of trans fat and stick to your healthy eating habits.]

Set a limit on trans fats to establish healthy eating habits

Though it's important to pay attention to your trans-fat intake, Wootan says, "you shouldn't avoid every single gram of trans fats at the expense of raising your intake of saturated fats. People are eating about five times more saturated fats than trans fats, so it's important to look at both."

Americans typically get about 54 calories, just 2.6 percent of their daily total, from trans fats -- slightly less than 6 grams. (One gram of fat -- trans fats included -- contains 9 calories, 5 more than a gram of protein or carbohydrate.) But when you add that to our average daily saturated-fat intake of about 24-30 grams, it's no wonder heart disease is the country's No. 1 cause of death.

Recommendations for healthy eating

Experts recommend restricting that artery-clogging combination of fats to less than 10 percent of total daily calories, or about 20-22 grams on an 1,800- to 2,000-calorie diet (20-22 grams have 180-198 calories).

For many, that's a tall order. "You can get a whole day's worth of trans and saturated fats in a single sitting," Wootan cautions. Order a Burger King Whopper with cheese, a medium chocolate shake and medium french fries and you've just consumed a whopping 40 grams of saturated and trans fats -- two days' worth! The french fries contain the most trans fats, 4.5 grams (in addition to 5 grams of saturated fats), while the Whopper with cheese has the most saturated fats, 18 grams.

But even if you never set foot in a fast-food joint, you can still inadvertently run up your trans-fat numbers. A bowl of Kellogg's Cracklin' Oat Bran cereal (1.5 grams of trans fats plus 2 grams of saturated fats) with 1 percent milk (1.5 grams saturated fat) for breakfast plus a Jell-O Pudding Snack (1.5 grams of trans fats plus 1.5 grams of saturated fat) uses up 40 percent of a day's allotment of trans fats and saturated fats combined.

Consumer-health advocates are hoping that once trans-fat numbers start appearing on labels, the food industry will be forced to reformulate their products, a process that is neither easy nor cheap. But in fact, changes are already happening: Frito-Lay removed the trans fats from its chips; Unilever Bestfoods has marketed a trans-fat-free line of Promise soft spread (tub) margarines; and seven of the eight varieties of Triscuit Baked Whole Grain Wheat Crackers (except Cheddar) contain no trans fats. Supermarkets such as Whole Foods Market and Wild Oats Natural Marketplace stock their shelves with snacks and baked goods that contain no partially hydrogenated vegetable oils.

It may be a long while before trans-fat-free foods go mainstream, though. Still, with the upcoming labeling laws, Wootan says, "at least people will finally know just how much heart-damaging fat is in their foods."

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