External cues such as packaging and container size can powerfully and unknowingly increase how much food a person consumes. Do they still, however, stimulate consumption as the perceived favorability of a food declines? This was examined with popcorn in a theatre setting. Moviegoers who had rated the popcorn as tasting relatively unfavorable ate 61% more popcorn if randomly given a large container than a smaller one. Moviegoers who had rated the popcorn as relatively favorable ate 49% more when the container size was increased (and were likely to eat greater amounts if accompanied with a person of the opposite sex). One reason for this increase was that consumers had more difficulty monitoring how much they ate from large containers. Implications for raising the consumption levels of healthy, but unfavorable foods are investigated. (C) 2001 Elsevier Science Ltd. All rights reserved.