Substituting snacks with strawberries and sudokus: does restraint matter?

OBJECTIVE: Prior research demonstrates that fruit/vegetables and sedentary activities can serve as substitutes for high-calorie snack foods, when the behavioral costs for obtaining snack food increase. The current study investigated if fruit/vegetables are better substitutes for snacks than sedentary activities are and whether individual differences in dietary restraint play a role in how snacks are being substituted.

DESIGN: Participants (n = 59) performed a concurrent schedules task, in which fruit/vegetables, sedentary activities, and snacks were simultaneously available. The response requirement for earning snacks increased per trial. Afterward, dietary restraint was measured.

MAIN OUTCOME MEASURES: The amount of responses for snacks per trial and the amount of points earned for fruit/vegetables and sedentary activity per trial.

RESULTS: When snacks are harder to obtain, participants increased working for both fruit/vegetables and sedentary activities. No differences were found for dietary restraint in the way snacks were substituted. However, high-restrained participants worked harder for snack foods than low-restrained participants.

CONCLUSION: Fruit/vegetables and sedentary activities are both equally viable substitutes for high-calorie snacks. High-calorie snacks have a higher reinforcing value for highly restrained eaters.