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

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?

Boosting Self-Control of Unsuccessful Dieters

The reviewed research implies that increasing dieting goal accessibility in unsuccessful dieters should boost their ability to resist food temptations. Indeed, dieters are more successful when they are reminded of their dieting goal. For instance, dieters more often chose an apple over a Twix-bar as a gift when primed with dieting (Fishbach et al., 2003), and dieters ate less snacks after exposure to diet-products in television commercials (Anschutz, Van Strien, & Engels, 2008). However, in these studies only short-term responses were assessed and the experimenter provided the diet-reminders. For unsuccessful dieters, it would actually be more efficient if they could prime themselves with the dieting goal in tempting situations. One recent study (Van Koningsbruggen, Stroebe, Papies, & Aarts, 2010) examined whether this may be achieved by using a specific planning strategy, the formation of implementation intentions