Psychosocial Influences on Fruit and Vegetable Intake Following a NYC Supermarket Discount

Abstract

Objective Assess the effect of a 50% discount on fruits and vegetables (F&V) on the purchase and intake of F&V and on psychosocial determinants of F&V intake: self-efficacy (SE), stages of change (SOC), and perceived barriers (PB). Methods This randomized controlled trial was conducted in local supermarkets over 16-weeks, including a 4-week baseline, 8-week discount intervention, and 4-week follow-up. Shoppers with overweight or obesity (BMI>25) were randomized to receive a discount or no discount via their reward scan card after the baseline. Twenty-four hour recalls and psychosocial measures were obtained for each study period. Results Purchases (p<0.0005) and intakes of F&V (p = 0.019) increased significantly during the intervention, only F&V intake was sustained at follow-up. The discount intervention increased SE (p<0.01) and SOC (p<0.05), and did not decrease PB (p = 0.057), during the intervention. SOC mediated the discount intervention effect on F&V intake (p<0.05) during the intervention, explaining 43% of variance. Conclusion A supermarket discount intervention led to increases in purchases and intakes of F&V, and the psychosocial factors SE and SOC, and did not decrease PB. The discount intervention prompted participants to move from the preparation to action stage of SOC, which acted as a mediator for increased F&V intake.

Improving Consumption and Purchases of Healthier Foods in Retail Environments: A Systematic Review

“…Promotion was the most commonly utilized marketing P and was the focus of 23 studies. Overall, 1 study had mixed effects (positive + negative) [ 16 ], 5 had mixed effects (positive + null) [ 17 , 18 , 19 , 20 , 21 ], 8 had mixed effects (positive + null + negative) [ 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 ], 1 had negative effects [ 30 ], 2 had null effects [ 31 , 32 ], and 13 had positive effects [ 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 ], (see Table 2 ).…”

“…Three studies implemented price-only interventions [ 18 , 29 , 33 ]. One study had mixed effects (positive + null + negative) [ 29 ], while another had mixed effects (positive + null) [ 18 ] and one study had only positive effects [ 33 ].…”

“…Three studies implemented price-only interventions [ 18 , 29 , 33 ]. One study had mixed effects (positive + null + negative) [ 29 ], while another had mixed effects (positive + null) [ 18 ] and one study had only positive effects [ 33 ]. Both experimental studies provided a 50% discount for fruits and vegetables [ 18 , 33 ] and found that customers who received the discount purchased significantly more fruits and vegetables than customers who did not receive the discount [ 18 , 33 ].…”

“…One study had mixed effects (positive + null + negative) [ 29 ], while another had mixed effects (positive + null) [ 18 ] and one study had only positive effects [ 33 ]. Both experimental studies provided a 50% discount for fruits and vegetables [ 18 , 33 ] and found that customers who received the discount purchased significantly more fruits and vegetables than customers who did not receive the discount [ 18 , 33 ]. However, one study also found no sustained effect on participants’ spending on fruits and vegetables from baseline to follow-up period [ 18 ].…”

“…Both experimental studies provided a 50% discount for fruits and vegetables [ 18 , 33 ] and found that customers who received the discount purchased significantly more fruits and vegetables than customers who did not receive the discount [ 18 , 33 ]. However, one study also found no sustained effect on participants’ spending on fruits and vegetables from baseline to follow-up period [ 18 ]. In addition, one study used a pre-experimental design [ 29 ].…”