Four fat rules.

Don't run from fat, rule it. These four rules show you how.

In less than a minute, Christina Huggle of Sedan, Kansas, can reel off the names of more than a half dozen of her school and other activities. Too pressed for time to pack a lunch in the morning and bored with the school's selections, Christina punches lunch from a vending machine. Dinner--sometimes as late as 9 or 10 p.m.--is whatever she can find in the fridge, healthful or not.

"I know about nutrition," the 16-year-old says. "I just don't always have the time to take account of it."

If you're like Christina, you like the idea of eating healthfully--especially when it comes to eating fats. But you don't want to have to think too much about it. So here's some good news: Science World has boiled down what you need to know about fats into four simple rules.

Rule 1

You need some fat.

Fat isn't a four-letter word. It's a nutrient, a substance that gives nourishment and aids growth. Like the body's other four essential nutrients--proteins, carbohydrates, vitamins, and minerals--fats perform many jobs, from providing energy for sports to helping your body absorb vitamins A, E, D, and K. (These vitamins aid with blood clotting, absorbing calcium, forming red blood cells, and more.) Fats also keep your skin glowing and your hair glossy.

Fatty acids--molecule chains that make up fat--consist of a long "backbone" of carbon atoms. The worst fat offender--the saturated fatty acid--has hydrogen atoms stuck to every carbon atom. Saturated fat (found in butter, for example) hardens at room temperature. Monounsaturated fats, like olive oil, have fewer hydrogen atoms and tend to be liquid at room temperature.

Rule 2

Not all fats are equal.

All fats contain 120 calories per teaspoon. But different fats affect your body in different ways, especially when it comes to cholesterol (see chart on page 9). Cholesterol is a waxy molecule the liver produces and is also found in some foods. It is not a fat.

In the past, when doctors measured heart health, they looked at a person's total cholesterol level. Now another measurement is a much more important factor. This is the ratio of your bad LDL cholesterol to your good HDL cholesterol. (Bad LDL cholesterol tends to catch along artery walls and harden--with other particles--into dangerous plaque that blocks blood flow. Good HDL cholesterol collects bad cholesterol and carries it back to the liver, where it can be broken down.)The less bad LDL and the more good HDL you have, the lower your risk for heart disease.

Rule 3

Thirty percent or less.

You need fat, you just don't need a lot of it. That's because fat packs a mean caloric punch. There are 9 calories in a gram of fat versus 4 calories in a gram of protein or carbohydrates. (A gram of fat equals one fifth of a tablespoon.)

Too much fat contributes to clogged arteries, heart disease, and strokes. And these conditions can start to develop when you're young. If you eat lots of greasy foods, ugly fatty streaks may already be building up in your arteries. Eating too much fat saps your energy and can add up to extra pounds. Researchers also suspect links between fats and some cancers.

Today, health experts recommend you keep the amount of fat in your diet to 30 percent or less of your daily calories. Here's a simple formula to help figure this out:

What's 30% of your daily calories? This formula tells you:

(insert your weight) X .45 =  your target
                              number of daily fat grams

Using this formula, someone who
weighs 140 pounds shouldn't
exceed 63 fat grams a day.

Once you know this number, check out food labels
you eat for several days; include labels available at counters
of fast-food restaurants. Add up the fat grams you
eat for each of those days. You'll see how your fat
consumption measures up.

A Shortcut

* Check the "percent daily value" (DV) column on food
labels. If you aim for products whose daily value of fat
is low--less than 5 percent--you'll be more likely to
end up with 30 percent or less in fat calories. If the
products you choose contain high daily values of fat--20
percent or more--you're more likely to miss your
target and consume too much fat.

Sample Food Label:

Nutrition Facts

% Daily Value(*)

Total Fat 2.5g      4%

Rule 4

Substitute
healthful fats for
less healthful ones.

To get more healthful fats into your diet,
try to increase the amount of mono- and
polyunsaturated fats and decrease the
amount of saturated fats and trans-fatty
acids in your diet (keep in mind Rule 3).

Each day, for example, try to substitute
one healthful fat for one less healthful one. Here
are some tips:

* Use canola or olive oil when cooking instead of
butter, margarine, or other oils.

* Look for snacks in which the word hydrogenated
(process that turns unsaturated fat into
saturated fat) is not listed among the top four
ingredients.

* If you eat fast-food french fries, choose the
smaller size. "It's doing something good for your
body not to put unhealthy fat in it," says Leslie
Bonci, a dietitian at the Center for Sports
Medicine in Pittsburgh, Pa.

* Cut the amount of butter, margarine,
mayonnaise, and salad dressings you use in half.

* Try to eat more fish, Albacore tuna with
low-fat mayonnaise is a good bet. The American
Heart Association has just officially
recommended you eat two 3-oz. servings of
fatty fish--like salmon or sardines--a week
for maximum heart health.

Fat lurks beneath everyone's skin! What does it
really look like? Check out these fat cells magnified
236 times. Each glob is linked by connective tissue,
flexible cell that support body structure.

TYPES OF fat

What do different fats do, anyway?
This chart shows you.

Types of fat           Form                    Main sources

1. SATURATED           Hard at room            Foods from animals
                       temperature             (meat, poultry, and
                                               dairy foods such as
                                               cheese and ice
                                               cream); and palm
                                               and coconut oils

2. MONO-UNSATURATED    Liquid at room          Olive oils, canola
                       temperature             oil, avocados, nuts

3. POLY-UNSATURATED    Liquid at room          Soybean oil, corn
                       temperature             oil, safflower oil

4. TRANSFATTY ACIDS    Starts as a polyun-     Stick margarine,
                       saturated (liquid)      vegetable shorten-
                       fat and is hardened     ing, commerically
                       through a chemical      fried foods, and
                       process into a solid    packaged baked
                       that behaves like       goods
                       a saturated fat

5. OMEGA-3             Liquid (a special       Fish, particularly
                       form of polyunsat-      albacore tuna,
                       urated fats that        salmon; walnuts
                       has unique effects)

Types of fat           Effects

1. SATURATED           Negative. Raises blood levels of
                       bad LDL (which stands for low-
                       density lipid, or fat) cholesterol.
                       Cholesterol, a fatty molecule
                       produced in the liver, helps the
                       body produce vitamin D and
                       absorb fats. But too much
                       cholesterol clogs arteries.

2. MONO-UNSATURATED    Positive. Lowers bad LDL
                       cholesterol blood vesels. Raises
                       good HDL (high-density lipid)
                       cholesterol blood levels.

3. POLY-UNSATURATED    Mixed. Generally lowers bad
                       LDL levels, but also lowers good
                       HDL levels. Research suggests
                       highly polysaturated fats
                       (like safflower oil) can trigger
                       changes in the body that
                       increase cancer risk.

4. TRANSFATTY ACIDS    Negative--a double whammy.
                       Raises bad LDL levels and lowers
                       good HDL levels. The body may
                       have difficulty breaking down
                       these fats, so they hang around,
                       increasing heart disease risk.

5. OMEGA-3             Positive. Protects against heart
                       disease; helps keep heartbeat
                       steady; acts as an anti-inflamma-
                       tory, easing muscle aches; helps
                       protect against the growth of
                       some tumores; critical for nerve-
                       cell transmissions in the brain.
                       (Researchers are exploring
                       whether a lack of omega-3s in
                       the body is linked to conditions
                       such as depression and atten-
                       tion-deficit disorder.)

Just the Fats, Ma'am!

Are you limiting the amount of fats you eat? Are you substituting healthful fats for less healthful ones? To sort fat from fiction, circle a number for each question. Then add up your total and check your score below.

How often do you eat

                          seldom or   1-2 times   3-5 times   almost
                            never      a week       a week     daily

1. fried, deep-fried,         1         2            3          4
or breaded foods?

2. whole milk,                1         2            3          4
ice cream, or
high-fat cheese?

3. baked goods                1         2            3          4
(not fat free)?

4. fatty meats, Such as       1         2            3          4
bacon, sausage, cold
cuts, and hot dogs?

5. hamburgers                 1         2            3          4
(not of lean meat)?

6. chips and other            1         2            3          4
high-fat snack foods

7. tuna or other fish?        4         3            2          1

8. food cooked in              4         3            2         1
olive or canola oils
versus another oil?

9. nuts or peanut              4         3            2         1
butter?

10. soft or squeezable         4         3            2         1
margarine?

Your Score

10-20: You're winning the heart-healthy sweepstakes--keep up the great work. Just remember, you do need some fat in your diet.

21-30: You understand the basics, Aim for small changes in your diet that improve your "heart-healthy" lifestyle,

31-40: You're fat-happy, Break the greasy chains that bind you! Reread Rule 4.

Cross-Curricular Connection

Social Studies: Choose two or three countries in other parts of the world and research what foods are eaten.

Did you Know?

* If you take in more calories than you expend--regardless of whether the calories come from fat, protein, or carbohydrates--the unused energy is converted and stored as excess body fat.

* Eliminating fat from your diet can be dangerous! However, modest decreases in dietary fat, like substituting low-fat milk for whole milk, can be healthy. Major dietary changes should be monitored by a doctor.

* In America, the main source of saturated fat comes from meat, milk, and bakery products.

National Science Education Standards

Grades 5-8: structure and function in living systems personal health * risks and benefits

Grades 9- 12: the cell * personal and community health * matter, energy, and organization in living systems

Resources

The Healthy Refrigerator: www.healthyfridge.org

The American Heart Association: www.americanheart.org

U.S. Dietary Guidelines: www.health.gov/dietaryguidelines

CHECK FOR UNDERSTANDING

Name:

Directions: Match the word(s) on the left column with the correct definition at the right.

--1. cholesterol

--2. saturated fats and trans-fatty acids

--3. monounsaturated and polyunsaturated fats

--4. nutrients

--5. fatty acids

a. substances that give nourishment

b. molecule chains that make up fat

c. waxy substance produced by the liver and found in some foods

d. fats that lower bad LDL cholesterol levels

e. unhealthful fats that raise bad LDL cholesterol levels

ANSWERS

Four Fat Rules

1. c 2. e 3. d 4. a 5. b