During this launch period, 16-year-old Austin K., of California, Md., bit into a cream-filled pastry that practically oozed fat. Austin joked that the rich dessert was “a heart attack wrapped in plastic.” But it tasted so good! Should he have trashed the treat?

The abundance of information about fats, trans fats, and lowfat diets in the news and in ads is enough to give teens like Austin a big fat headache. What’s the real story? Is it OK to eat fats, or should you steer clear completely?

Fats: Oh No or OK?

“Your body needs fats to be healthy,” explains Roberta Anding, a spokesperson for the American Dietetic Association and a registered dietitian at Texas Children’s Hospital in Houston. As a matter of fact, some fats are good; they give your body energy and help it absorb nutrients such as vitamins A, D, E, and K. As you might guess, other fats are not so good. Eat too much of those and not only will you find it tougher to fit into your jeans, but you could also be paving the way to heart disease, obesity, and even cancer.

So if, like Austin, you treat yourself to a fatty food today, skip the guilt trip–but know your limits. Teens should keep fat intake to between 25 percent and 35 percent of total daily calories, according to the 2005 Dietary Guidelines for Americans. One gram of fat equals 9 calories. If you typically consume 2,000 calories per day, then you need between 56 and 78 grams of fat. (You might need fewer calories if you don’t get much physical activity, more if you exercise a lot.)

Choose Wisely

The key to sorting through confusion about fat is to learn about the different kinds and to make smart decisions about which ones to consume. That surprises Kathleen L., 14, of Oaks, Pa. “I’ve never thought about fats as a good thing,” says Kathleen, who is studying nutrition in her cooking class at school. The three main types of fatty acids have different effects on levels of cholesterol. Cholesterol is a fatty substance in the blood and tissues of the body. Although cholesterol is important for your health, it can sometimes pose health problems.

Unsaturated fats, such as monounsaturated and polyunsaturated fatty acids, don’t raise cholesterol levels. Some studies suggest that unsaturated fats might help lower LDL cholesterol.

Saturated fats raise the amount of harmful cholesterol (LDL) in the blood. This type of cholesterol clogs arteries and can increase the risk of developing heart disease.

Trans fats raise LDL cholesterol levels, possibly even more than saturated fats do. Trans fats also tend to lower the healthy kind of cholesterol (HDL). Nutrition officials say there is no safe amount of trans fats–avoid them as much as possible.

Plan Ahead

It’s not always easy for teens to be smart and choosy about fats, especially when a busy schedule leaves no time to eat well. Skipping meals may lead to an intense desire for fatty foods, says Jean Antonello, the author of Naturally Thin Kids. “Kids [who] crave double cheeseburgers because of excessive hunger are probably not interested in watching the type of fat they are taking in.”

“Eat as healthy as possible when you’re at home and friends aren’t around,” suggests Robert Kowalski, the author of The New 8-Week Cholesterol Cure. “Before you go out to a party, have a handful of grapes or trail mix. You’ll be less likely to eat too much of the high-fat foods that are often served.”

It might seem like too big a hassle to eat healthily, but the effort pays off. “Heart disease starts in childhood and expresses itself in adulthood,” says Anding. (For more on this killer, read “Breaking the Heart” on page 26.) “Filling up with saturated or trans fats puts sludge in the arteries that contribute to heart disease. Nobody puts sludge in their car’s gas tank and expects good performance. Our bodies work the same way.”

FAT FINDER

A look at the fats in your favorite foods

UNSATURATED FATS

OK amount: At least 36 grams, or two-thirds of total daily fat intake

Mostly in oils from plants. Polyunsaturated fats are in nuts, corn, soybeans, and their oils. Fish such as salmon and tuna contain polyunsaturated fats as well as omega-3 fatty acids, which protect against heart disease. Monounsaturated fats are present in canola oil, olive oil, peanut oil, avocados, and almonds.

SATURATED FATS

OK amount: Less than 26 grams, or one-third of total daily fat intake

Occur mostly in animal products, such as meat, butter, cream, cheeses, and other dairy products made from whole milk. Saturated fats are also found in tropical oils such as coconut oil and palm kernel oil.

TRANS FATS

No acceptable amount

Found in many kinds of margarine, crackers, baked goods, and other foods made with or fried in partially hydrogenated oils (such as French fries and store-bought cookies)

JUST THE FACTS

You can easily determine a food’s fat content by reading the Nutrition Facts label. Since Jan. 1, 2006, the Food and Drug Administration (FDA) has required food manufacturers to list trans fat alongside total fat and saturated fat. But beware: Manufacturers are allowed to add half a gram of trans fat per serving to their foods and still boast “zero trans fats.”

“Look at the ingredient list,” advises nutrition expert Robert Kowalski. “If ‘partially hydrogenated oil’ is listed, assume … half a gram has been added.”

“Choose the food you like that has the lowest amounts of saturated fat and trans fat listed on its label,” advises dietitian Roberta Anding.

LOOK AT FATS

This macaroni and cheese seem healthy enough. With 12 grams of fat and 3 grams of saturated fat, it appears acceptable for a teen’s diet. But watch out! See those 3 grams of trans fat? That’s 3 too many!

THE BIG PICTURE The bottom of the label shows how the fats above fit into daily totals.

Discuss

* Are fats good or bad for you? (Both. Your body needs some fat for energy, help in absorbing nutrients, and other processes. But the wrong kinds of fats can predispose you to heart disease, obesity, or cancer.)

* If you typically consume 2,400 calories per day, what should your fat intake be? (Between 600 and 840 of your daily calories should come from fat; that’s about 67 to 93 grams of fat.)

* You’re deciding between two snacks: a candy bar or a bag of peanuts. How can you make a healthy choice? (Answers will vary but may include the following: Compare the fat content on each product’s label, look at the ingredient list for sources of unhealthy fat, estimate your fat total for that day and how much you can “spare. “‘)

Do

Ask a local dietitian to speak to your class. He or she can provide more information about the differences between various fats, the good and harm they can do, and the foods in which they are found. Have the dietitian suggest ways in which students can replace the unhealthy fats in their diets. Bring in a recipe for a high-fat treat, like fudge brownies or nachos with the works, and ask the speaker to modify its fat content to be healthier. Then make the treat for the class (or ask for a volunteer to do so) so students can see how tasty healthy food can be!