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

These lines of research suggest that it is difficult for dieters to resist temptations because tempting food cues trigger the hedonic goal of eating enjoyment, while inhibiting the dieting goal. Does this really influence behavior? Yes! There is a great deal of research showing that accessible goals can have a strong influence on people’s behavior and that priming desirable goal states triggers motivated behavior to reach that goal (e.g., see Aarts, 2007). Moreover, numerous studies have already demonstrated that dieters are more likely to overeat when exposed to tempting food cues. Research inspired by the goal conflict model increases our understanding of the psychological processes underlying these findings. Think back, for example, to the “pizza study” of Fedoroff and colleagues (1997), who demonstrated that priming participants with the smell of pizza increased pizza consumption for dieters. Smelling tasty pizza is likely to prime eating enjoyment for dieters. Consequently, the dieting goal is inhibited, while thoughts about eating enjoyment are flooding the mind of dieters. Moreover, dieters evaluate pizza more positively and perceive it as bigger than without pre-exposure to the pizza smell. These processes are likely to have made it very difficult for dieters to resist the temptation of eating the high-caloric pizza. Fortunately, not all dieters fail.

Why Some Dieters Succeed

Whereas the goal conflict model of eating (Stroebe, 2008) offers an explanation for why dieters often fail, the theory of temptation-elicited goal activation (Fishbach, Friedman, & Kruglanski, 2003) suggests that tempting food cues can also initiate processes that should lead to successful self-control. Fishbach and colleagues (2003) suggested that there are successful dieters for whom temptations increase the cognitive accessibility of long-term goals that are typically undermined by these temptations. They argue that a facilitative link between temptation and goal develops when people repeatedly and successfully exert self-control in tempting situations. For instance, if you have been able for some time to say no when offered a piece of cake on birthday parties because you are on a diet, a link between cakes and dieting may develop. The next time that you are exposed to cake you should automatically activate your dieting goal which should make it easier to turn down the piece of cake.

Indeed, research showed that when participants were primed with tempting food, the accessibility of the dieting goal was increased for those who were weight concerned and perceived themselves to be successful dieters (Fishbach et al., 2003). Perceived success was measured by asking participants to indicate the extent to which they were successful in watching their weight, in losing weight and how difficult they found it to stay in shape. However, you may have noticed that these findings contradict the goal conflict model and earlier research (Stroebe et al., 2008) as weight-concerned participants did not inhibit the dieting goal. Subsequent research using the Fishbach-measure of success and a lexical decision task to assess the accessibility of the dieting goal following tempting food primes resolved this inconsistency by showing that tempting food cues inhibit the dieting goal in unsuccessful dieters, but activate this goal in successful dieters (Papies, Stroebe, & Aarts, 2008b). These differences in dieting goal accessibility between unsuccessful and successful dieters have recently been found to impact both perceptual processes and dieters’ intention-behavior relationship.

For instance, Van Koningsbruggen et al. (in press) not only assessed size perception of muffins, but in another study asked participants to estimate the size of an apple: Food instrumental for reaching the dieting goal. Results showed that the tempting food prime increased the perceived size of the apple for successful dieters, but decreased it for unsuccessful dieters. Perceiving healthy food in the environment as bigger (vs. smaller) increases (vs. decreases) the likelihood that these foods are detected and consumed. However, when exposed to a dieting magazine–increasing dieting goal accessibility for both unsuccessful and successful dieters–all dieters perceived the apple as bigger.

In another study (Papies et al., 2008b), dieters reported their intentions to refrain from eating several palatable foods the next two weeks. Two weeks later, they were asked how often they had eaten the foods. Results revealed that only successful dieters acted in line with their good intentions. For them, intentions predicted behavior, such that stronger not-eating intentions corresponded with eating them less. Unsuccessful dieters did not act according to their intentions: Intentions did not predict behavior. Moreover, in this and the Van Koningsbruggen et al. (in press) study, successful dieters had a lower Body Mass Index, suggesting they are also successful in the long term.

Thus, some dieters appear successful in pursuing their diet and controlling food intake when tempted. While most tend to forget their dieting goal when tempted, successful dieters spontaneously think of dieting. Knowing this, is it possible to help unsuccessful dieters to become more successful?