HEALTH WATCH
Cut Calories Without Eating Less
By Nancy Ross Ryan
Eat more, weigh less. Sound too good to be true? According to Barbara Rolls, Ph.D., author of this year's Volumetics (HarperCollins), you can indeed consume a greater volume of low-energy-dense foods without increasing calories. And the greater volume leads to a feeling of fullness, or satiety. And, as we all know, feeling hungry is one of the biggest obstacles to successful dieting. Beyond that, gaining back lost weight is one of the biggest disappointments after a successful diet. This new approach -- which, of course, includes regular exercise -- promises that you can feel full, lose weight and sustain that weight loss over time. And the theory is based on research done by Rolls at the University of Pennsylvania, and Dr. Roland L Weinsier, M.D., at the University of Alabama at Birmingham.
Rolls holds the endowed Guthrie Chair of Nutrition at Pennsylvania State University, has spent more than 20 years researching hunger and obesity, and has written three academic books on food and nutrition. This is her first book for the general public.
Some of her findings: That we all tend to eat the same weight of food at our meals, day after day. But it makes a big difference in calories if that same weight is food that is low in energy density. And, perhaps more surprising, fat does not determine satiety or a feeling of fullness. "When we first started this study, we thought that fat played an important role in satiety. We found that, when you keep the calories and volume of food that a person eats fairly constant, you don't see any special effects for fat in terms of reducing hunger. Fat can taste good, but it doesn't necessarily make you feel satiated." she says.
What is energy density? Simply put, given the same weight of food, gram for gram, foods low in energy density have fewer calories, foods high in energy density have more. For example, one gram of fat has nine calories, one gram of carbohydrates and protein have four calories each. But it's not quite that simple. It's the combination of elements in a food -- fat, carbohydrate, protein, fiber and water -- that determines energy density. Two examples: 1/4 cup of raisins and 1-2/3 cups of fresh grapes each have 100 calories, but no fat. Which fat-free food makes you feel fuller? One fresh garden tomato has 25 calories; so do fat free pretzels -- but only 1/4 ounce of them, about 5 tiny pretzel sticks. Ounce for ounce fat-free pretzels have about 20 times as many calories as tomatoes. (Notice that both grapes and tomatoes are high in water content and fiber. Raisins are high in fiber but low in water content. Fat-free pretzels are low in water content and fiber.)
Rolls believes that energy density -- or calories in grams, expressed in a single number -- is so important that it "Should be added to every food that carries a nutrition label."
The Volumetrics system works like this:
Dr. Roland L. Weinsier was the first to look at the relationship of energy density and weight loss. He has been helping people lose weight at the University of Alabama for the past 25 years using these principles. "Hunger is a critical issue," he says. "We eat according to the weight of food, not calories or fat content. If I eat French fries, a soda and a cheeseburger -- a high-energy-density meal -- by the time I have eaten enough weight to feel full enough to get the signal to stop, I have over eaten on calories. But if I eat that same weight in a meal composed of whole grains, fruit and vegetables, by the time I get the signal from my body to stop I may have not even eaten enough calories to meet my body's caloric needs."
He began his program (still going strong today) -- switching participants from a high-fat, energy-dense diet to one lower in fat and energy density -- in 1976. In 1983 he showed that people who stayed on a low-energy-dense weight loss plan maintained the lost weight, and 80 percent of them were at their new lower body weight or below two years later. "The program is effective in people who are mildly overweight -- or massively obese. And it works in men and women," he says. Of course, he adds, "Twenty percent of the people put all their weight back and then some. They were total failures."
What accounts for those total failures? Neither Rolls nor Weinstein can say for sure. There are few long-term studies on weight maintenance and the role of exercise, and more are needed. But both feel that exercise is essential to weight loss and maintenance. And in her book Rolls stresses the importance of behavior modification.
"Change takes effort," she says. "If you're forty, and eat five meals and snacks a day, you've done so 70,000 times by now." Fortunately, weight management experts have developed behavior modification approaches that are proven to make permanent lifestyle change easier, and Rolls believes that if you use them, chances are you'll lose more weight than if you simply try to change your eating and exercise habits. "You'll also increase your chances of keeping the weight off," she says.
She says the seven most effective behavior modification strategies are:
But could a consistently high volume of albeit low-energy-dense food stretch your stomach? Can your stomach stretch or shrink? Rolls recommended putting those question to Dr. Allan Geliebter, M.D., a research psychologist at the obesity research center, St. Luke's Roosevelt Hospital, Columbia University, New York. According to Dr. Geliebter's research, stomachs indeed can stretch and shrink. His studies in bullemic individuals (who binge and purge), found that bullemics do have a larger stomach capacity over time. And, in studies done with individuals on a very low-calorie diet (600 calories a day), "There was a significant reduction of stomach capacity -- by 30%." Geliebter recommends "Two strategies. First eat low-energy-density foods, but have smaller meals, and more meals a day, maybe more than three."
Rolls cautions that there is no magic bullet to quick weight loss. "People want to lose weight and look like movie stars without any work. There is no nutrient that makes fat magically melt away." And she recommends that the best way to lose weight is to consume 500 fewer calories a day while increasing physical activity. That leads to a weight loss of about one pound a week. "Losing one to two pounds a week is the best rate for long-term success. Lose weight faster, and you'll simply regain much of it."
All of which is true, but old news. The new news is that you can very possibly do it without feeling hungry.
Energy Density in Foods
CALORIES
New weight management strategy tames hunger with low-energy-density diet.
SPECIAL TO THE TRIBUNE
May 10, 2000
1. Keep a food and exercise log: Studies show keeping food records is the best predictor of successful weight loss.
2. Identify and manage cues for overeating and underactivity: If you're a chocoholic who likes to eat it while watching TV in the living room, keep it out of the house entirely, or buy just two pieces, not a pound, and decide to eat in another room.
3. Work on constructive thoughts and feelings: Instead of, "I had a donut, now I've blown my diet," how about, "O.K., so I ate a donut; I can still make healthy choices the rest of the day and wind up with a good eating day."
4. Learn stress management: If you overeat in response to stress, it's easy to override your satiety signals. Some techniques to calm down include deep breathing, progressive muscle relaxation, meditation, exercise.
5. Get more involved with family and friends: People who have more social support do better in weight management.
6. Exercise! Do something on a regular basis to move.
7. Make a plan to handle setbacks: Some days are better than others, no one loses weight every day. It helps to think ahead how you're going to handle eating situations that trigger diet relapses.
Here's how it's figured (calories divided by grams equals Energy Density):
Very low-energy-dense foods: Less than 0.6 E.D., includes most fruits and vegetables, skim milk, and broth-based soups.
Low-energy-dense foods: E.D. 0.6 to 1.5, includes many cooked grains, breakfast cereals with low-fat milk, low-fat meats, beans and legumes, low-fat mixed dishes and salads.
Medium-energy-dense foods: E.D. 1.5 to 4.0, includes meats,cheeses, high-fat mixed dishes, salad dressing, some snack foods.
High-energy-dense foods: E.D. 4.0 to 9.0, includes crackers, chips, chocolate candies, cookies, nuts, butter, and full-fat condiments.
How Much Is Enough?
To calculate how many calories you need to maintain your present weight without gaining or losing, first decide if you are sedentary (little or no physical activity on a daily basis); or moderately active (you expend 150 calories a day in physical activity, the equivalent of walking about two miles). Now multiply your weight in pounds by the appropriate number below:
Sedentary woman: 12
Sedentary man: 14
Moderately active woman: 15
Moderately active man: 17
Example: If you are a moderately active woman who weighs 150 pounds, multiply 150 x 15=2,250, the number of calories you need to maintain your current weight. How Much is Too Much?
If you are that 150-pound woman who needs 2,250 calories per day to maintain current weight, but eats 500 more calories per day, or 2,750, at the end of a week you will have gained one pound. 3,500 extra calories equals one extra pound. Conversely, if you reduce your caloric intake by 500 to 1,750 calories daily, at the end of a week you will have lost one pound.
