Licensing Effect

Drop a bunch of kale into your cart and you’re more likely to head next to the ice cream or beer section. The more “virtuous” products you have in your basket, the stronger your temptation to succumb to vice.

Such hedonic balancing acts are neither unpredictable — who, after all, hasn’t rewarded themselves with a piece of cake or an extra beer after a killer workout? — nor inherently bad. But an emerging body of research into what psychologists call the “licensing effect” suggests that this tit-for-tat tendency is deeply wired in us, operating even when we’re not aware of it. And in a world where we’re bombarded by pitches for an endless array of health-boosting products of dubious efficacy, that can be a problem.
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So how can we maximize our chances of coming out ahead? Psychologists have identified a few tactics.

One is to focus on the process of living healthfully rather than the goal of being healthy. A recent University of Zurich study tracked the progress of 126 dieters and found that, as predicted by licensing theory, the more weight the subjects lost in any given week, the less weight they would lose (or the more they would gain) the following week. But this rebound effect was weakest when the subjects homed in on the process of changing their eating behavior rather than on the outcome of losing weight or improving their appearance.

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