HEALTH HORIZONS : NUTRITION : Weight a Minute! : Your scale may not lie, but it doesn’t tell you the whole truth. Carrying less fat is the key.

Don’t you just want to pick up the bathroom scale and heave it out the window sometimes? Here you are, trying your best to exercise regularly and, darn, if that needle doesn’t refuse to bobble downward. You feel more energetic. Your clothes fit more loosely. Your doctor even says your blood pressure and cholesterol are down.

Why doesn’t your body weight go down? You’re about ready to give up on the healthy resolutions, retreat to the couch with a jumbo package of fudge-dipped Double Stuf Oreos and watch reruns of “Bonanza” and “The Brady Bunch” for the rest of your years.

Forget what the scale’s needle tells you. You are already healthier because a combination of exercise and good nutrition lowers your percentage of body fat. Carrying less fat, not less weight, is the key to good health and the bottom line to your bottom line, fitness and health experts now agree.

“Extra fat really has no use,” said Los Angeles-based exercise physiologist and personal trainer Douglas Brooks. ‘It’s just an extra weight the body has to transport. It just makes us a less-efficient machine.’

Excess fat also invites a list of deadly diseases including heart attack, diabetes and stroke, as well as risks that can add up to cardiovascular disease, such as elevated blood pressure, cholesterol and insulin levels.

Your risk shoots even higher if you have what some call “Michelin’s Disease,” or a spare tire of fat around the middle. Men typically gain fat there, while women normally gain fat lower around their hips and thighs. Fat apparently finds its way into the blood stream easier from the midsection.

A certain amount of fat is essential to protect organs and to maintain certain body functions. The essential stuff is OK. An average healthy woman carries four times as much essential fat--the stuff buried deep around reproductive organs, in breasts and laced through muscle--as does a man. Add a few pounds of fat stored underneath the skin and total percent of body fat for a woman in good health reaches 22-25%. A fit man in good health is 15-18% fat.

“You are going to jiggle,” said Covert Bailey, international lecturer on weight management and author of several books including “Fit or Fat” and “Fit or Fat Target Diet.”

Figuring out whether you’ve got more than your share of fat is the first step to finding out how your health ranks. Forget the scale because it counts everything, including bones and organs, so that number tells you very little, Brooks said.

Here’s how fat changes happen: Your body is made up of bones, water, muscle, internal organs and fat. If you start to lower the amount of fat inside with exercise and low-fat, high-carbohydrate meals, you might look the same from the outside at first. But your insides? Leaner, healthier. Your body composition-the ratio of lean to fat-has changed, but your body weight has remained nearly the same.

If, however, you make the needle on the scale drop with diet alone, your ratio of body fat to lean could actually go up because you’ve lost muscle, a typical mistake made by crash dieters.

You don’t have to wait long for the benefits of diet and exercise either, according to a study published recently in the American Journal of Cardiology. he research, led by UCLA nutrition professor R. James Barnard, found health gains in 72 obese subjects after only three weeks on an exercise program and low-fat, high-complex-carbohydrate diet at the Pritikin Longevity Center in Santa Monica.

Although all of the subjects remained overweight, all lowered their levels of blood insulin, triglycerides (fats in the blood) and blood-pressure-all factors that increase the risk of heart disease. Many subjects found during the short-term study that the diet and exercise program allowed them to stop taking their medicine for diabietes or high blood pressure.

Exercise physiologists or fitness professionals in health clubs or sports rehabilitation centers can pinch and poke in just the right places to calculate your body fat.

As depicted on the preceeding page, there are other methods to assess your body composition and health.

Work your way through a few of these to determine your real measure of good health.

How to Estimate Your Target Body Weight

You can estimate your desired body weight by using your percentage of body fat.

Follow the example below:

1. Your weight in pounds: 150

2. Body fat percentage (from skin fold measurement): 22%

3. Fat weight (your weight times item 2): 150 x 0.22 = 33 pounds

4. Lean body weight (your weight minus item 3): 150 - 33 = 117 pounds

5. Desired percentage of body fat: 17%

6. Desired weight (item 4 divided by (1.00 minus item 5): 117 / (1-0.17) = 141 pounds

7. Pounds to gain or lose (your weight minus item 6): 150-141 = 9 pounds

*

NOW ESTIMATE YOUR DESIRED BODY WEIGHT

1. Your weight in pounds

2. Body fat percentage (from skin fold measurement): %

3. Fat weight (your weight times item 2): pounds

4. Lean body weight (your weight minus item 3): pounds

5. Desired percentage of body fat: %

6. Desired weight (item 4 divided by (1.00 minus item 5): pounds

7. Pounds to gain or lose (your weight minus item 6): pounds

Source: American College of Sports Medicine, Indianapolis