EFFECTS OF LEARNED FLAVOR CUES ON SINGLE MEAL AND DAILY FOOD-INTAKE IN HUMANS

This study examined the effects of learned flavor cues on lunch-meal a nd daily food intake in 39, normal-weight, free-living adults. Subject s were fed distinctly flavored high-calorie (HC) and low-calorie (LC) milkshake preloads. Following the repeated flavor-calorie pairings, th e flavors of the milkshakes were covertly switched. Twenty-three perce nt of the participants were classified as sensory responders. That is, their lunch intake reflected the anticipated caloric content of the p reloads based on the sensory properties rather than the true energy va lue. Short-term sensory learning did not reliably alter 24-h energy in take in these subjects. The remaining subjects (i.e., sensory nonrespo nders) ignored the flavor cues and consumed the same size lunches acro ss all phases of the study. Compensation for the preloads was examined during the training period (i.e., before the flavors were switched). Sensory responders accurately adjusted lunch intakes on the first day of exposure to both preloads, demonstrating unlearned compensation for energy density. Compensation continued to be accurate across training days for the HC (85%) but not the LC preload (65%). Sensory nonrespon ders did not compensate accurately for either of the preloads. Thus, s ensory responders were initially more responsive to the caloric densit y of the preloads and continued to make accurate adjustments when the flavor cue matched the caloric load (i.e., during training) but were m isled by the flavor cue when it did not match the caloric consequence (i.e., when the flavors were switched). Sensory nonresponders ignored the sensory cues and ate the same size lunches regardless of the calor ic value of the preload. However, sensory nonresponders corrected for this discrepancy by adjusting their intake later in the day. These dat a suggest that individuals might use different strategies to guide the ir food intake.