Ten Tips for Staying Lean
1. Curb calorie density
Does fat make you fat? For years, popular diet books assured the chubby masses that a low-fat diet was the key to weight loss. They were right…and wrong. “Our research shows that it's calorie density—not fat—that determines how many calories people eat,” says Susan Roberts of the Jean Mayer U.S. Department of Agriculture Human Nutrition Research Center on Aging at Tufts University in Boston. For 18 days, Roberts offered 14 people meals that were either low-fat (20 percent of calories from fat) or high-fat (40 percent fat). But, unlike other studies comparing high-fat and low-fat diets, these two regimens had the same amount of fiber, palatability, and calorie density (that's a food's calories divided by its weight). “When we kept calorie density constant, people on the high-fat diet ate no more calories than people on the low-fat diet,” says Roberts. But her research doesn't let fat off the hook, because it's so calorie-dense. “Fat is important to watch out for, but low-fat foods that are high in sugar like SnackWell's cookies and Entenmann's cakes are also high in calorie density,” says Roberts's colleague Megan McCrory. The bottom line is that low-fat diets that are loaded with vegetables and fruits and other high-fiber, low-calorie foods may indeed help keep the pounds off. Diets filled with calorie-dense low-fat cakes, cookies, ice cream—and even bread, pasta, and crackers—may not.
2. Shrink your servings
“When people were served larger portions of lasagna, they ate more than when they were given smaller portions and allowed to get up for more,” says Tufts's McCrory. That's what happened in single-meal studies done decades ago. More recent studies show that when people are given larger amounts of “hedonistic” foods like M&Ms, they eat more than people who are given smaller amounts. “When we gave people big buckets of popcorn—the ones you have to hold with two hands—at a movie theater, they ate 40 to 50 percent more popcorn than people who got smaller buckets,” says Brian Wansink, director of the Food and Brand Research Lab at the University of Illinois at Urbana-Champaign. The only exception: Women on a date ate the same amount of popcorn, regardless of bucket size, he notes. When they were on their own or with friends, though, watch out. The nation is proving those studies right. “Serving sizes in restaurants have gotten bigger,” says Marion Nestle of New York University. “Food is low in cost relative to rent and labor,” she explains. “So it's just as easy to throw in more food.” And it's tough to change. “People become accustomed to large amounts, so if they're served a normal portion they feel cheated,” says Nestle. That could explain why people who frequent restaurants are more likely to be overweight. “We asked people how many times they ate at different restaurants, like Chinese, Mexican, or places that serve pizza, hamburgers, fried chicken, or fried fish,” says McCrory. “The more often they ate out, the fatter they were.” It may be more than huge portions that make restaurant-goers heavier. “Restaurants serve foods that are calorie-dense, palatable, varied, and in large portions,” says McCrory. And that's a recipe for flab. The answer, says Nestle, is simple: Eat less. “Before you put the first fork in, think about how much you're going to eat and have them wrap up the rest for the next day,” says Nestle, who recently dropped ten pounds to lower her blood cholesterol. (It fell 60 points.) “It really works.”
3. Limit (some) choices
“Eat a variety of foods,” says the government's Dietary Guidelines for Americans, the American Dietetic Association, and others. “But variety may be the dieter's enemy,” says McCrory. “People eat more pasta if they have three shapes to choose from, even if all three are the same color and they're served with plain spaghetti sauce,” she says. Lack of variety may help some people lose weight on the Atkins diet or other regimens that limit bread, pasta, rice, potatoes, and other carbohydrates. Suddenly, variety plummets to a much narrower—and more manageable—range. “The instinct to eat a variety of foods is incredibly powerful,” says Tufts's Susan Roberts. “We probably wouldn't have survived in Paleolithic times if we weren't programmed to eat meat, fruit, and vegetables instead of just one food.” McCrory and Roberts found that people who eat the widest variety of almost any food—including sweets, pizza, sandwiches, salad dressings, pasta, and potatoes—have more body fat. (More variety means typically eating eight rather than three kinds of sandwiches, six rather than two kinds of cookies, etc.) Exceptions: people who eat a variety of fruits and dairy products have no more (or less) body fat. And people who eat the widest variety of vegetables have less body fat than others. “Vegetables are good news for people who are trying to reduce their weight,” says Roberts. “They're low in calorie density, so they may displace calorie-dense foods, and their bulk may reduce overeating.” Yet just five vegetables—fresh potatoes, frozen potatoes, onions, iceberg lettuce, and processed tomatoes—make up half of all the vegetables we eat, says McCrory. Instead of a variety of vegetables, many of us eat a variety of junk. “If you want cookies, you're better off buying three boxes of one kind than one box each of three different kinds,” says McCrory. “With just one kind of cookie in the house, you get sick of it after a while.”
4. Curb liquid calories
Ate more than you should have? No problem. You'll just eat less later. That's more likely to happen if the extra calories you ate came from solid rather than from liquid foods, says Richard Mattes of Purdue University. He gave 15 normal-weight men and women an extra 450 calories a day as either a liquid (three 12-ounce cans of soda) or solid (45 large jelly beans) for four weeks each. “When they got the solid food, they ate less at other times, so they adjusted for all of the calories,” he explains. In contrast, “when they got the liquid food, they just added those calories to their customary diet. They didn't compensate at all.” Other studies also suggest that people compensate best for solid foods, less well for semi-solid foods like (non-clear) soup or milkshakes, and worst for liquids, he adds. “Liquid calories don't trip our satiety mechanisms,” says Mattes. A recent analysis of a national survey jibes with his findings. “The more (non-diet) sodas children drink, the more calories they consume,” he notes. The solution: “Use beverages that have no calories,” Mattes suggests.
5. Make movement part of your life
This doesn't necessarily mean tennis or bicycling. Gardening, raking leaves, mowing the lawn, and washing windows also count. “Overweight people are more amenable to increasing lifestyle activities—like using the stairs or parking farther away from the mall—than going to the gym,” says Thomas Wadden, an obesity expert at the University of Pennsylvania. And people who boost their lifestyle activity are just as successful at keeping the weight off as people who participate in formal exercise programs. In fact, overweight children lose more weight when told to limit sedentary activities than when told to exercise (or to do both). “Getting kids to turn off the TV or spend less time at the computer works better than urging them to increase their aerobic activity,” says Wadden.
6. Exercise for weight maintenance
Exercise doesn't make much difference when you're trying to lose weight. “Fairly strenuous exercise—30 to 40 minutes three or four times a week—produces only a two to six pound weight loss over six months,” says Wadden. That's because exercise just doesn't burn that many calories and because some people may compensate by eating more. “Most people who participate in an exercise program think, ‘I should look like Cindy Crawford by now,’” he says. But that's unrealistic. It's not weight loss, but weight maintenance, that gets easier when people exercise. “If you find 100 people who have kept the weight off, 90 of them are likely to be exercising enough to burn more than 1,500 calories a week,” says Wadden. Rena Wing of the University of Pittsburgh has enrolled 2,000 people in her National Weight Control Registry. These weight-loss champs—who report having lost an average of 66 pounds—expend an average of 2,800 calories a week. That's the equivalent of walking three or four miles a day. Who has the time? “Most of the people in our registry don't do only one thing,” says Wing. On average, they spend about 1,000 calories a week walking. That's ten miles. But most combine that with other activities.“That's the flip-side of limiting your variety of high-calorie foods,” she adds. “For physical activity, we encourage variety” so people don't get bored.
7. Break it up
Note to busy folks: People who exercise in shorter bouts may be more likely to stick with the program. “If you tell people they have to exercise for 40 minutes a day and warm up and cool down, some say they don't have 40 minutes and that's the end of it,” says Wing. “But if you say, ‘try to find ten minutes four times a day,’ they say, ‘OK, maybe I can do ten minutes after my lunch break or while I'm waiting for the pasta to cook’.” And even if they don't squeeze in all four bouts, they may get in two or three.
8. Find a friend
For many people, eating less and exercising more is easier if they don't go it alone. “It's an old strategy,” says Rena Wing. “In some early weight-loss studies, they put people at a worksite on different teams to compete against one another. It works because the people on the team support each other and the competition is fun.” Wing does caution, however, that “groups don't always work. When we treated husbands and wives together, we weren't very successful. It seemed to help the wife, but the husband did less well.” One can only speculate as to why. But in general, it makes sense that healthy living loves company. Would you rather be watching your weight in a crowd that's munching on baby carrots or pigging out on pizza? And even the most airtight excuse for avoiding exercise can evaporate when someone asks you to go for a walk or run.
9. Set realistic goals
How much weight can you expect to lose? A few years ago, Tom Wadden and colleagues asked 60 obese women—they averaged 218 pounds—their “goal weight,” “dream weight,” “happy weight,” “acceptable weight,” and “disappointed weight.” After 48 weeks of treatment, the women lost an average of 35 pounds…slightly less than their “disappointed” weight loss (37 pounds). Half never even lost that much. Almost all fell far short of their “acceptable” weight loss (55 pounds). “Most people have unrealistic expectations,” says Wadden. “People can typically reduce their weight by 10 to 15 percent with the best behavior-modification programs. If you try to lose 20 or 30 percent, you're likely to regain the weight.” The body seems to defend its weight, he adds. “But there's a certain amount of wiggle room.” Go beyond it and you set yourself up to fail. “Satisfaction is comparing what you expect and what you get,” says Wadden. “If you keep ratcheting up your expectations, you'll get dissatisfied and quit.”
10. Think healthy, not just skinny
Diet sodas, Wow chips, and artificially sweetened candy bars may help you cut calories, but healthy they're not. Each time you chew on a high- or low-calorie candy bar you miss a chance to swallow some phytochemicals neatly packaged in a wedge of watermelon or a handful of berries. Luckily, the same foods that cut your risk of cancer, heart disease, diabetes, and stroke should help you trim extra padding between your shoulders and knees. Don't think of them as punishment. Dishes like roasted asparagus, stir-fried broccoli, sautéed mushrooms, or broiled pineapple or bananas can be delicacies. Skinny isn't the only point of exercise, either. You can be fit and fat…if you move enough. “When we looked at overweight men as a group, they were less physically fit and had the highest death rate,” says Steven Blair of the Cooper Institute of Aerobics Research in Dallas. “But when we looked separately at the overweight men who were fit, we didn't see much increase in dying.” The same probably holds for women. To be fit, you have to accumulate at least 30 minutes of moderate-intensity activity most days.
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