Information about the fat content of preloads influences energy intake in healthy women.

OBJECTIVE: This study tested the hypothesis that the perceived fat content of a preload (a required first course) influences subsequent food and energy intake. SUBJECTS AND
DESIGN: Forty-eight healthy, nondieting women (24 restrained, 24 unrestrained) were given a fixed amount (350 g) of three different yogurts (low-fat, low-calorie; low-fat, high-calorie; high-fat, high-calorie), or no yogurt, followed by lunch (30 minutes after the yogurt preload was served) and dinner (4.5 hours later). Each subject was tested in all four conditions in a counterbalanced design. Half of the subjects received accurate information, in the form of a label, about the fat content of the yogurts, which did not necessarily correspond to energy content; the other half received no information. ANALYSES: Energy intake, the percentage of macronutrients in the meals, and subjective sensations of hunger and satiety were analyzed.
RESULTS: No effect of restraint was noted in the intake analyses. A significant information-by-preload interaction (P < .05) was found. Subjects who had information consumed more energy at lunch after eating a preload labeled low fat than after eating a preload with similar energy content but labeled high fat. The opposite response was seen in women who did not receive information. When energy consumed at dinner was included in the analyses, overall intake was still significantly greater in the women who received information and ate a low-fat preload. No differences were found in the percentage of macronutrients selected or in subjective sensations after consumption of any of the preloads.
CONCLUSIONS: Messages about the fat content of a food can influence energy intake in healthy women.