Perceived healthiness of food. If it's healthy, you can eat more!

The main aim of this study was to investigate the effects of food-related beliefs about the healthiness of foods, restrained eating, and weight salience on actual food intake during an ad libitum snack. In a 2 (healthy vs. unhealthy) by 2 (restrained vs. unrestrained eaters) by 2 (weight salient vs. not salient) factorial design, 99 female undergraduate students were invited to taste and rate oatmeal-raisin cookies. Dietary restraint and weight salience did not influence snack intake, but participants ate about 35% more when the snack was regarded as healthy than when it was seen as unhealthy. Ratings of the snack food's "healthiness," "capacity to affect weight" and "appropriateness in a healthy menu" also indicated that the "healthy" manipulation was effective. In addition, the "weight salience" manipulation appears to influence perceptions about food differently in restrained versus unrestrained eaters, in that restrained eaters rated the snack food more negatively than unrestrained eaters did when they received weight feedback before eating. Beliefs about the healthiness of foods may thus be of great relevance to both food intake and weight gain.