Daily consumption of individual snack foods decreases their reinforcing value.

The reinforcing value of food is one factor that influences energy intake. The purpose of this study was to determine if the reinforcing value of highly liked snack foods could be modified by restriction or daily intake of individual preferred foods in the absence of changes in total energy intake. Food reinforcement was tested at baseline and after each of two, two-week phases. During the restriction phase, participants did not eat a target food or closely related foods while during the daily intake phase, participants consumed a 200-300 kcal portion of the target food daily. The reinforcing value of the target food significantly decreased after two weeks of daily intake. Restriction did not change food reinforcement. These data suggest that eating a portion of a highly palatable food every day decreases its reinforcing value. Implications for weight control are discussed.