Consistent relationships between sensory properties of savory snack foods and calories influence food intake in rats

Objective: Determine the influence of experience with consistent or inconsistent relationships between the sensory properties of snack foods and their caloric consequences on the control of food intake or body weight in rats. Design: Rats received plain and BBQ flavored potato chips as a dietary supplement, along with ad lib rat chow. For some rats the potato chips were a consistent source of high fat and high calories (regular potato chips). For other rats, the chips provided high fat and high calories on some occasions (regular potato chips) and provided no digestible fat and fewer calories at other times (light potato chips manufactured with a fat substitute). Thus, animals in the first group were given experiences that the sensory properties of potato chips were strong predictors of high calories, while animals in the second group were given experiences that the sensory properties of potato chips were not predictors of high calories. Subjects: Juvenile and adult male Sprague-Dawley rats. Measurements: Following exposure to varying potato chip-calorie contingencies, intake of a novel, high-fat snack food and subsequent chow intake were assessed. Body weight gain and body composition as measured by DEXA were also measured. Results: In juvenile animals, exposure to a consistent relationship between potato chips and calories resulted in reduced chow intake, both when no chips were provided and following consumption of a novel high-fat, high-calorie snack chip. Long-term experience with these contingencies did not affect body weight gain or body composition in juveniles. In adult rats, exposure to an inconsistent relationship between potato chips and calories resulted in increased consumption of a novel high-fat, high-calorie snack chip premeal along with impaired compensation for the calories contained in the premeal. Conclusion: Consumption of foods in which the sensory properties are poor predictors of caloric consequences may alter subsequent food intake.