Nutrition interventions at point-of-sale to encourage healthier food purchasing: a systematic review

BACKGROUND: Point-of-sale is a potentially important opportunity to promote healthy eating through nutrition education and environment modification. The aim of this review was to describe and review the evidence of effectiveness of various types of interventions that have been used at point-of-sale to encourage purchase and/or eating of healthier food and to improve health outcomes, and the extent to which effectiveness was related to intensity, duration and intervention setting. METHODS: Records from searches in databases were screened and assessed against inclusion criteria. Included studies had risk of bias assessed. Intervention effectiveness was assessed for two outcomes: i) purchase and/or intake of healthier food options and/or nutrient intake; and ii) mediating factors that might effect the primary outcome. RESULTS: The search identified 5635 references. Thirty-two papers met the inclusion criteria. Twelve studies had low risk of bias and were classified as strong, nine were moderate and 11 were weak. Six intervention types and a range of different outcome measures were described in these papers: i) nutrition education and promotion alone through supermarkets/stores; ii) nutrition education plus enhanced availability of healthy food; iii) monetary incentive alone; iv) nutrition education plus monetary incentives; v) nutrition intervention through vending machines; and vi) nutrition intervention through shopping online. The evidence of this review indicates that monetary incentives offered to customers for a short-term look promising in increasing purchase of healthier food options when the intervention is applied by itself in stores or supermarkets. There was a lack of good quality studies addressing all other types of relevant point-of-sale interventions examining change in purchase and/or intake of healthier food options. There were few studies that examined mediating factors that might mediate the effect on the primary outcomes of relevant interventions. CONCLUSIONS: A range of intervention types have been used at point-of-sale to encourage healthy purchasing and/or intake of healthier food options and to improve health outcomes. There is a need for more well designed studies on the effectiveness of a range of point-of-sale interventions to encourage healthier eating and improve health outcomes, and of the mediating factors that might impact these interventions. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/1471-2458-14-919) contains supplementary material, which is available to authorized users.