Don't clean your plate!

Philip J. Goscienski, M.D.

December 2011

Scientists who study our eating habits and those of our children have made some interesting observations but they haven't done a good job at getting the word out. If they did we might get a better handle on our love handles.

When an adult places food on the plate for preschoolers they eat about as much as they do when they are allowed to fill their own plates. That is, they leave food behind when they are full. As they get older, however, they are more likely to eat everything that is put on the plate. Most of us remember that when we were children Mom usually decided how much to serve and she encouraged us to finish it all. The "clean plate club" was a dinnertime mantra, right up there with what those starving kids in China would be lucky to have. Unfortunately, Chinese families are getting plenty of food these days and obesity is skyrocketing there.

Long before most of us reach adulthood the visual cues that drive our food intake override the internal signals of satiety. Some persons stop eating when they are full. Others sail right past that point, apparently because they pay more attention to visual cues than to internal ones.

The "soup experiment" makes the point. Researchers arranged for an ingenious system that allowed soup bowls to refill automatically as the subjects ate. When the participants in this trial ate about as much soup as a normal bowl would hold, they kept on eating as the bowl refilled itself. When I read the report I couldn't help thinking that the researchers must have had some way of distracting the subjects, or that the latter were a particularly unobservant group. The study was no fluke, however, since there have been several variations of it. Most of us have noticed that we tend to eat more in social situations, sometimes because of an overindulgent hostess but usually because we imitate those around us, most of whom are overweight.

One strategy for dieters is to serve meals on small plates, providing the culinary optical illusion that more food is present. Another is to note how many servings there are in packaged food. Some bags of snacks contain 1½ servings — and who would even consider leaving a half-serving behind?

It's not easy to ignore visual and social cues that encourage overeating. Perhaps we should follow the example of those preschoolers.

Philip J. Goscienski, M.D. is the author of Health Secrets of the Stone Age, Better Life Publishers 2005. Contact him at drphil@stoneagedoc.com.