Research paper
Rolls BJ, Roe LS, Meengs JS. The effect of large portion sizes on energy intake is sustained for 11 days. Obesity (Silver Spring). 2007 Jun;15(6):1535-43. doi:10.1038/oby.2007.182. PMID:17557991
Why we cite it
A controlled crossover study demonstrating that the portion size effect on energy intake is sustained over 11 days — participants do not compensate for excess consumption over time. Extends earlier 2-day findings to show that large portions represent a durable driver of overeating, not a novelty effect. This is one of the key non-Wansink portion size studies (see kwr01).