The aim of this paper is to assess existing evidence on how nudge (gentle push) interventions can lead people to a plant-based diet. In December 2017 a systematic literature search of articles published with PubMed, Scopus and Web of Science was carried out. The following search strategy was used: plant-based OR vegetarian OR vegan OR semi-vegetarian OR pro-vegetarian AND nudging OR choice architecture OR behavioral change OR behavioral intervention. Due to heterogeneous outcome
measures, it was not possible to perform a meta-analysis, so the results are presented in a narrative style.
A total of 425 articles were found, of which 8 met the inclusion criteria. Six studies were rated as of good quality. All the articles, except one, suggest that the push in general exerts a positive effect on the consumption of foods of vegetable origin. The nudge, to provide a predetermined option, seems to be the most promising for the promotion of plant-based consumption in food service operations.
Nudging appears to be effective in promoting a plant-based diet by facilitating healthier choices. Interventions that use predetermined options (for example, previously weighed portions, option without meat, etc.) seem to be particularly effective. However, future studies should provide the size of the actual effect of their interventions and the long-term effects at the consumer level.