Food label granularity and working memory: effects on food choice in a randomized controlled trial

Compared with the control condition, food labels reduced mean calorie selection by 4.56%. Each one-unit increase in 3-back performance resulted in an additional 14 kcal reduction under coarse labels and 18 kcal under detailed labels. Individuals with high working memory capacity exhibited a preference for moderate-calorie products over the lowest-calorie products when detailed labels were displayed. The effects of capacity under coarse labels were less pronounced and primarily limited to avoiding the lowest-calorie option. These findings provide conceptual insights into information optimization and offer practical guidance for policymakers on designing effective FOP schemes by specifying when detail helps versus hinders consumer choice.