Overweight

Overweight

Take Aim at a Slimmer Shape

Judging from the tidal waves of low-fat foods washing up on supermarket shelves and the multitude of health clubs popping up in cities, you'd think that America had become the land of the lean and the home of the fit.

Not by a long shot. In fact, one in three Americans--the highest number ever--is now seriously overweight, the National Center for Health Statistics in Bethesda, Maryland, has reported. Experts call obesity an epidemic--and it's one that's spawning major health problems in women. Heart disease, endometrial cancer and possibly breast cancer, high blood pressure, high cholesterol, immune problems, gallstones, gout, diabetes, osteoarthritis, stroke and sleep apnea are all associated with overweight.

But do we really know what our healthiest weight is? How many of us are on target? And what are those who are on target doing differently from those who aren't?

To answer these questions, Prevention Magazine surveyed women readers and got more than 10,000 responses. Here's an overview of the survey results.

Frustrations of Fat-Fighting

Frustration fairly leaped off the pages of the responses. Ninety percent of the respondents confessed they needed to lose weight (on average, 27 pounds). Only 14 percent described themselves as "well-toned," and just 7 percent said they were "very satisfied" with their bodies. More than half admitted they were "not very" or "not at all" satisfied.

But are so many female fat-fighters really overweight, or do we just want to look slimmer?

In the opinion of top medical researchers and experts on obesity, many of the respondents had valid reasons for being concerned about their weight.

"Slimmer is definitely healthier," observes William P. Castelli, M.D., medical director of the famed Framingham Heart Study, which followed 5,000 Massachusetts residents for 40 years to assess their risk for heart disease.

Fortunately, researchers are exploring ways to evaluate optimal body weight based on the latest research on weight-related health risks. Two approaches, used together, are emerging as the new "gold standard" for such evaluations: body mass index and waist/hip ratio.

An Index of Your Risk

Body mass index (BMI) is a ratio of height to weight. It's determined by a mathematical formula: First you divide your weight (in pounds) by your height (in inches) squared, then multiply the resulting number by 705. You should get a BMI that's somewhere between 19 and 30. But you don't have to do the calculations: just see "Calculating Your BMI" on page 396.

Several large medical studies, involving thousands of people, have suggested that 21 to 22 is the optimal BMI. At this level, there are no weight-related health risks, according to Dr. Castelli.

One large-scale study that points to a BMI below 22 as ideal for preventing heart disease in women is the Nurses' Health Study, based at Harvard University and Brigham and Women's Hospital in Boston. In it, researchers followed 115,886 initially healthy American women ages 30 to 55 for eight years. During that time, 605 of the women experienced coronary artery disease, leading to 83 deaths.

There was no elevated risk of heart disease among women whose BMIs were under 21 (the lean group). For women whose BMI was between 21 and 25, the risk of heart disease was 30 percent higher. It was 80 percent higher for women with a BMI between 25 and 29. And women whose BMI was greater than 29 had more than twice the risk of heart disease (230 percent) of those with a BMI under 21.

"Obesity is a strong risk factor for coronary heart disease in middle-aged women," the researchers concluded. "Even mild-to-moderate overweight is associated with a substantial elevation in coronary risk." Other large-scale studies have reached similar conclusions.

Safety Measures

Beyond heart disease, there seems to be a broader safety range. A BMI between 23 and 25 isn't ideal, some experts insist, but the excess risk for cancer and other weight-related diseases seems to be small at that level. Around a BMI of roughly 26, these health risks appear to rise, although scientists don't agree on exactly where to draw the line.

Most scientists do agree that a BMI over 27 increases risk for many people. But risk also depends on other factors, including waist/hip ratio, notes Jean Pierre Despres, Ph.D., associate director of the Lipid Research Center at Laval University in St. Foy, Quebec.

Researchers have determined that the fat most associated with health risks is on the upper body--the abdomen and above--rather than on the thighs and hips. (A pattern of upper-body fat is often called central obesity.)

Some Hip Calculations

One way to judge whether you have too much upper-body fat is by measuring your waist (at the midpoint between your bottom rib and your hipbone) and your hips (at their widest point). Then divide the waist measurement by the hip measurement. The resulting number is your waist/hip ratio (WHR).

If your waist is 30 inches and your hips are 37 inches, for example, you would divide 30 by 37 to get a WHR of 0.81.

What's an ideal WHR? While scientists quibble over hundredths of a percent, most target 0.80 or less as desirable for both women and men.

This technique isn't very reliable for women who are very thin or very overweight. But in most cases, it can prove very predictive of cardiovascular disease risk.

"Central obesity is turning out to be the most lethal risk factor associated with excess body weight," says Dr. Castelli. That's because upper-body fat is strongly correlated with visceral fat, which is fat that's packed around our internal organs.

While more of the research on the health risks of upper-body fat has been done with men, more research with women is beginning. Researchers at the University of Miami School of Medicine and the University of Minnesota School of Public Health, for example, examined data on 32,898 healthy women ages 55 to 69. In a four-year period, there were nearly three times as many heart disease deaths among women with the highest WHR (over 0.86) as among women with the lowest.

A high WHR has also been associated with diabetes, hypertension, breast and endometrial cancers and high cholesterol.

Dr. Castelli is one of several scientists who believe that WHR is even more important than BMI in predicting risk. "If someone has a healthy body mass index but a high WHR, it is important to try to bring that WHR down," he explains. "Someone with a higher BMI but a low WHR might not be quite as bad off."

Overweight or Overfat?

According to weight-control experts, some women may be confusing overweight with overfat. If you're in the "optimal" range, you may not need to lose pounds. But even so, you may need to lose fat and improve muscle tone.

Along with BMI and WHR, muscle tone does have relevance to health risks and weight. After all, scientists agree that the danger of overweight generally is not from heavy bones or muscles; it's from excess fat.

Exact standards don't exist for how much body fat a person can carry without increasing risk, but at the Cooper Aerobics Center in Dallas, they aim for 18 to 22 percent of total weight as optimal for women, slightly higher than for men.

Unfortunately, it's not easy to determine percentage of body fat. There are several ways to go about it, from pinching skin folds with calipers to bioelectric impedance (running a mild current through the body to measure resistance) to underwater weighing. These methods are not widely available outside health clubs or specialists' offices and are not always reliable.

But you can often eyeball it, according to Joan Marie Conway, Ph.D., research chemist at the U.S. Department of Agriculture (USDA) Human Nutrition Research Center in Beltsville, Maryland. An easy way to judge whether you're overfat is by looking in a mirror, she explains. If, despite good BMI and WHR numbers, you look flabby, you probably are. And you'd do well to embark on an exercise regimen that burns fat and tones muscle.

Through all the weighing and measuring, it's important not to get too hung up on the scale or measuring tape, she adds. "You could never use one number to tell someone their risk for disease," says Dr. Conway.

Other doctors agree. "There are other factors, like family history, good and bad health habits like smoking and exercising or personal health risks like high cholesterol, low HDL cholesterol (the good kind) or high blood pressure to consider, too," says Dr. Despres. "People with more risk factors must be more careful of their weight."

Clearly, finding your perfect weight for health is not yet a precise science. But it's safer to err on the side of slender, says Dr. Castelli. "You may be on the borderline today, but where are you going to be five years from now? Get in the habit of controlling your weight before you have a problem, not after."

Flexing Your Way to Success

Many of the women who responded to the Prevention survey found that weight loss wasn't so hard. The toughest challenge, many said, was keeping the weight off. For them, exercise was an important factor. Forty-eight percent of the women with optimal weight were in the habit of exercising four or more times weekly.

Based on the experience of these women, here are some exercise tips that will help you go the extra mile.

Stretch your exercise time. "It's known that the only way to maintain weight loss forever is to increase the amount of physical activity you do," says Miriam Nelson, Ph.D., research scientist at the USDA Human Nutrition Research Center on Aging at Tufts University in Boston.

"People with desk jobs think, `I walk up and down stairs a lot and I run around doing household chores in the evening--I get plenty of exercise'; even if that adds up to 90 minutes of physical activity, it's not enough," says Dr. Conway. "You need intentional exercise like fitness walking or cycling to call yourself anything but sedentary."

Indeed, though women of optimal weight were no more active in their daily lives than overweight respondents, they did participate in more intentional exercise. In the optimal weight group, most women said their workout sessions lasted between a half-hour and an hour. Severely overweight women most commonly report the shortest exercise sessions--less than 20 minutes.

Go for pleasure. To exercise consistently, of course, you must find a form of exercise (or a combination of exercises) that you actually enjoy. "It needs to be something people like and feel they can continue doing indefinitely," says James O. Hill, Ph.D., associate director of the Center for Human Nutrition at the University of Colorado Health Sciences Center in Denver.

For people at risk from overweight, Dr. Despres recommends walking, walking, walking. The risk of injury is lower than for many other exercises. "We have shown that this is an excellent form of exercise to decrease excess abdominal fat and the complications associated with it," he explains.

"Even if you don't lose a lot of weight, your risk profile will improve with a brisk 45-minute walk four or five days a week," he continues. "If you don't exercise that much, you won't burn enough fat to get the substantial improvement in your risk profile that you'd see with that program."

Weight up. The Prevention survey also revealed that women who have optimal body weight do more strength training. Thirty-five percent of those in the optimal group were hefting small weights or using resistance machines to strengthen muscle, compared with 14 percent or fewer of those in heavier groups.

Why is strength training so important to maintaining healthy body weight? "Large muscle mass helps burn calories," Dr. Nelson explains. "More muscle means a faster metabolism." That's because muscle requires more oxygen and more calories to sustain itself than fat does. And strength training is more effective than aerobic exercise at building and maintaining muscle.

Some Food Advice

Of course, low-fat eating goes hand-in-hand with exercise. "When you combine strength training and aerobic exercise with sensible eating, you'll look trimmer, feel more fit and be able to eat more," observes Wayne Westcott, Ph.D., strength consultant to the YMCA of USA, IDEA: International Association of Fitness Professionals and the American Council on Exercise.

But how do you find comfortable limits without going on a diet? Here are the strategies recommended by experts.

Learn your body signals. Have you lost the ability to distinguish between emotional and physiological hunger and just plain boredom? If you have, your best bet to dump those unnecessary pounds and maintain a stable weight is to tap into what your body wants and doesn't want, says Steven C. Strauss, M.D., an internist in New York City specializing in nutrition and weight control and author of The Body Signal Secret.

As you eat, become aware of how you feel when you're satisfied, when you're full and when you're stuffed, Dr. Strauss advises. Then decide to stop eating whenever you hit the full mark. "If you eat only when you're hungry and stop when you're satisfied, your body will reach its optimal weight," says Dr. Strauss.

Multiply meals, shrink portions. If you're a devotee of three meals a day, you may be consuming more calories than you need at those meals and storing the rest as fat. That's because "your body can only use a certain amount of calories at a time to function," says Debra Waterhouse, R.D., author of Outsmarting the Female Fat Cell. Eating four or five mini-meals a day will prevent the problem.

Break the morning fast. "Never, ever eliminate breakfast," says Dr. Strauss. "Try to eat grains, fresh fruits and vegetables."

If "just a cup of coffee," is your basic M.O. for starting the day, your metabolism is probably sluggish, burning fewer calories than it should from subsequent meals. Since our bodies burn calories at a slower rate while we sleep, breakfast acts as reveille for our metabolism. In fact, a study at George Washington University in Washington, D.C., showed a metabolic increase of 3 to 4 percent above average in morning eaters.

Fill up on fiber. "High-fiber foods promote a feeling of fullness more readily than low-fiber meals," says Dr. Strauss. So "you feel more satisfied with less food."

Try hot oatmeal for breakfast, vegetarian chili for lunch and five-bean casserole for dinner. Aim for 35 grams of fiber a day. (For good sources of fiber, see page 122.)

Forgo excess fat. Fat calories are much harder to burn than calories from carbohydrates and proteins. They're also easily converted to body fat. "When you eat fat calories your body doesn't need, only a tiny fraction are used to digest and metabolize the fat; the rest store themselves in your fat cells," says Dr. Strauss. That's why you should keep fat calories to 25 percent or less of your daily diet.

How? First, avoid deep-fried or breaded and fried foods. Instead, go for broiled, grilled or baked fish and skinless chicken. Use a nonstick pan or oil sprays or chicken broth for sautéing. Try evaporated skim milk as a substitute for whole milk or cream.

Also, be sure to trim the fat off all meats before cooking. And for sweet treats, reach for fruit and nonfat products. Just be sure to read labels and check how much fat is in each product. "If the percentage of fat is greater than 15 percent, you may want to replace that item on the shelf," says Dr. Strauss.