FRIDAY, Dec. 6, 2002 (HealthDayNews) -- Almost no one can stop eating after just one normal serving if their plate has extra food -- regardless of whether they served themselves or were given a pre-filled plate.
A new study comes just in time to help those facing holiday buffets and family dinners be more aware of the tendency to gobble down huge portions.
A team led by Barbara Rolls, a nutrition researcher at Pennsylvania State University, gave 51 normal-weight and overweight men and women, aged 21 to 30, lunch one day a week for four weeks in the university laboratory. Each week, the subjects were served macaroni and cheese in one of four portion sizes, ranging from 2.5 cups to 5 cups. One group served themselves, while another was served plates filled with food.
All participants, whether served food or self-served, ate more when more food was available -- but they didn't feel any fuller despite eating more, Rolls found.
"The bottom line is, if you give people bigger portions they are going to eat more, " Rolls says. "They are not aware [of it]. And they are not going to feel fuller if they eat more."
If they did that in the laboratory, she predicts the situation will probably be much worse in the real world. At a restaurant, for instance, food is plentiful, people are often socializing and drinking, and the attention paid to portion size is likely to decline even more than in the lab, Rolls says.
Big portions aren't always undesirable, she hastens to add. "Reduce the calories in the food you are eating. Big portions of some foods can be a good thing. A salad with a low-fat dressing is good as a big portion." So are big portions of fruits and vegetables such as cantaloupe, carrots, blueberries, apples, and grapes that tend to fill a person up, she says.
Broth-based soups are good, too, in big portions. Rolls calls this strategy of eating large portions of foods low in calories and fat -- yet filling -- "volumetrics," as outlined in her books, including The Volumetrics Weight-Control Plan, due out in paperback soon.
Rolls observed that five people in each of the groups was a "plate cleaner," eating all but 30 grams of the macaroni and cheese. When she excluded them from the analysis, the effect of portion size was still there. The non-plate cleaner subjects in both the served and self-served groups consumed 27 percent more food when they were offered the largest portions compared with the smallest.
The study makes sense to Evelyn Tribole, a registered dietitian in Irvine, Calif., and author of the book Intuitive Eating, a paperback due out in 2003. Simply paying attention to what you are eating, without doing two or three other things at once, can help people be more aware of how much they are eating, she says. "We are so multi-tasking these days. Most people are eating and reading, or eating and working on the computer. If you really love food, you need to sit and savor and have the food experience."
Start out small to avoid overeating, Tribole advises. "Order a small stack of pancakes," she tells clients who need to lose weight. "They don't think it will be enough." But it often is.
What To Do
For information on portion sizes, try the American Dietetic Association or the Cleveland Clinic.
