magazine issue 10 2010 / Issue 11

Successful Dieting in Tempting Environments: Mission Impossible?

• written by Guido M. van Koningsbruggen, Wolfgang Stroebe & Henk Aarts
• edited by Hans IJzerman

Recent research provided support for the goal conflict model. One line of research (Papies, Stroebe, & Aarts, 2007) examined whether dieters indeed spontaneously think about eating enjoyment when exposed to tempting food cues. Cognitive accessibility of this eating enjoyment goal was measured with a lexical decision task in which participants had to decide quickly and accurately whether a word was an existing word or not. Although participants responded to many words, the researchers were especially interested in their reaction times to some words that reflected the eating enjoyment goal (e.g., tasty). In this task, faster recognition times of the eating enjoyment words (the time needed to indicate that “tasty” is an existing word) reflect greater cognitive accessibility of the eating enjoyment goal. Thus, if you often think about eating enjoyment you should be much quicker to decide that “tasty” is a real word than when you rarely think about it. Before participants had to make a lexical decision, they were exposed to cues signaling tempting food or not. They quickly read sentences involving consumption of tempting (e.g., “Jack eats chocolate”) or neutral food (e.g., “Jack eats raisins”) and then were shown the word to which they had to respond. Results demonstrated that dieters, but not normal eaters, were faster in deciding that words reflecting eating enjoyment were existing words when they read about palatable food before making this decision rather than neutral food. Tempting food cues thus activate the eating enjoyment goal in dieters which subsequently influences their eating behavior.

But does thinking about tasty food also let dieters forget their dieting goal? This was tested in another line of research (Stroebe et al., 2008) in which participants again had to do a lexical decision task after having been exposed to tempting food cues. But this time the researchers were interested in their reaction times to words that reflected the dieting goal (e.g., slim, weight). Importantly, just before participants had to make a lexical decision, they were exposed to tempting food words (e.g., chocolate) or neutral words (e.g., neither). These words were flashed so briefly (23 ms) that participants could not really recognize them. Thus, they were subliminally primed with the eating enjoyment goal or not. Results demonstrated that dieters, but not normal eaters, were slower to respond to dieting words when primed with eating enjoyment, suggesting that the eating enjoyment goal inhibits the dieting goal.

Moreover, these processes seem to further boost dieters’ positive evaluations of palatable food (Hofmann, Van Koningsbruggen, Stroebe, Ramanathan, & Aarts, in press) and affect basic perceptual processes (Papies, Stroebe, & Aarts, 2008a; Van Koningsbruggen, Stroebe, & Aarts, in press). For instance, Van Koningsbruggen and colleagues (in press) examined the impact of tempting food cues on size perception of food. In the food prime condition, meant to activate the eating enjoyment goal, participants were shown a cover of a culinary magazine depicting a tasty dessert. In the control condition, participants were shown a gardening magazine cover that was expected not to elicit thoughts about eating enjoyment. After some filler questions, participants had to estimate the size of an object as presented on a screen. They were unexpectedly shown a picture of a highly palatable food object: A chocolate muffin. Results showed that dieters, but not normal eaters, perceived the muffin as bigger when primed with the eating enjoyment goal. This enhanced size perception of “forbidden” foods increases the likelihood that palatable food items are detected in the environment and actually consumed.