The effectiveness of implicit interventions in food menus to promote healthier eating behaviours: A systematic review

Unhealthy eating and related chronic illness are serious public health concerns. Initial attempts to discourage unhealthy eating using explicit techniques have been largely unsuccessful. However, emerging implicit interventions have started to show promise. Common implicit interventions in food-choice contexts include placement, priming/cueing, defaults, naming, ratios, and signage. The present review aimed to evaluate the effectiveness of these interventions in promoting healthier eating behaviours in the context of food menus. Five electronic databases were searched. Included studies were conducted in a menu setting, used implicit interventions which were unlikely to be noticed by consumers, had a healthy-eating promotion focus, and were experimental or pre/post designs. A total of 19 papers comprising 23 individual studies were included. Overall, four of six implicit interventions effectively promoted healthier eating behaviours in one or more studies, with placement and default interventions the most promising. Priming/cueing and ratio interventions showed potential but require further investigation. Naming and signage interventions were largely unsuccessful, although this could be because they have not yet been explored in a variety of menu settings with a health-eating promotion focus. If existing findings can be extended to additional menu settings and demographics in future studies, implicit interventions could provide affordable and accessible tools to promote healthier eating.