Procedure
During recruitment, participants were asked to rate their attitudes toward
weight loss supplements. Attitudinal items were embedded in a faux questionnaire.
This study drew from previous work [12] to assess participants’ attitudes
toward weight loss supplements. Participants responded to “What do you
generally think about weight-loss supplements?” using a scale ranging from 1
(very unsafe/very bad/very unfavorable/very negative/very unhealthy/very invaluable/
very unnecessary) to 7 (very safe/very good/very favorable/very positive/very
healthy/very valuable/very necessary). Scores on these items showed internal
consistency (a ¼ 0.89). The mean of the seven items was computed to construct
an index measuring attitudes toward supplements. A high score indicated a
positive attitude toward weight loss supplements. Participants were told not to
take any dietary supplements on the day of study participation and to ensure that
they could enjoy a reward buffet at a student restaurant.
Upon arrival, participants were asked to help a faculty member in the Biology
Department with a functional food test to be used in a randomized, placebocontrolled
study. This department name was used to avoid participants guessing
the study purpose if they knew the author affiliations. After providing written