I know all about healthful eating and cutting calories to lose weight. But I just can't seem to sustain that kind of effort for long. What's wrong with me?
You are so not alone. And experts are beginning to understand why.
In a fascinating report published in the Centers for Disease Control and Prevention's journal Preventing Chronic Disease in January 2008, researchers provide persuasive evidence that food consumption is more influenced by our environment than our knowledge or our willpower.
The report, "Eating as an Automatic Behavior," describes numerous studies that support the notion that the amount and type of food we eat is strongly influenced by factors such as portion size, visibility and availability. For example, studies show that people given larger portion sizes of anything from baked pasta to potato chips to stale popcorn will eat much more of the food than people given smaller portions, yet they don't report feeling more full than those who ate less. Often, people will just continue to eat until the food in front of them is gone, no matter how large the portion.
One study showed that people ate fewer candies if they were stored in an opaque container than a transparent one. If the food is both visible and within arm's reach, it is more likely to be eaten.
Studies indicate that trying to overcome "automatic behaviors" can be done, but it takes a lot of mental energy. In one study, some participants were told not to eat the freshly baked chocolate chip cookies in front of them, then were asked to work on a difficult puzzle. They lasted only 8 minutes before giving up and reported feeling fatigued. The other participants -- those who either were allowed to eat the cookies or who weren't given cookies at all -- lasted 19 and 21 minutes, respectively.
That might explain why people tend to eat more during a meal if they're with other people than if dining alone -- 71 percent more if dining with six or more companions, according to one study. If we're distracted by conversation or involved in a social setting, we simply tend to eat more.
Most consumers tend to disregard the effect of environmental influences over their eating patterns, even when presented with strong evidence. But just being aware of this sort of automatic behavior can be helpful. Although it's difficult to control the foods and food messages you encounter in restaurants, stores and advertising, you can keep an apple or banana on your desk instead of a candy jar, and you can stock your refrigerator and pantry with easy-to-eat healthful foods instead of high-calorie options. Just reducing consumption by 100 calories a day would help shed pounds over time.
Chow Line is a service of Ohio State University Extension and the Ohio Agricultural Research and Development Center. Send questions to Chow Line, c/o Martha Filipic, 2021 Coffey Road, Columbus, OH, 43210-1044, or firstname.lastname@example.org.
Editor: To read the full report "Eating as an Automatic Behavior," see: http://www.cdc.gov/pcd/issues/2008/jan/07_0046.htm.
This column was reviewed by Julie Shertzer, registered dietitian and program specialist for Ohio State University Extension in the Department of Human Nutrition, in the College of Education and Human Ecology.