Overview: Unhealthy diet is a key modifiable risk factor for obesity and noncommunicable diseases (NCDs). Government policy is placing increasing emphasis on improving unhealthy diets by intervening at the environmental level to influence the behaviours of many people simultaneously.

Most UK families acquire food from supermarkets; consumers’ food choices in the supermarket environment are influenced by a range of factors including the availability and positioning of products. The National Institute of Health Research (NIHR) has funded researchers from the MRC Lifecourse Epidemiology Unit at the University of Southampton to evaluate the impact of product placement in supermarkets on the diets and product sales.

The WRAPPED study is a natural experiment being conducted with Iceland supermarket chain. The intervention will create a healthier store layout.

To date, this study is the largest supermarket trial internationally to assess the health impact of product placement in stores.

Objective: To examine whether increasing the availability of fresh fruit and vegetables and positioning them near the store entrance in discount supermarkets influences the purchasing and dietary patterns of women aged 18-45 years and their young children.

Methods: We will invite 1,620 women aged 18-45 years who regularly shop at one of 36 Iceland stores located across England to take part in the study. They will either shop at stores where the layout will change (intervention) or stores where it will remain the same (control).

Women will be surveyed once before the stores change, and three times afterwards to find out about the food they, and their young children (aged two to six years), usually eat, and their views on the supermarket environment. Women will also be asked to share the food purchasing information from their loyalty cards for the nine-month period of the study. We will look for differences in food purchasing and eating patterns between the women shopping at stores with the healthier layout and those using the unchanged stores. The results will tell us whether having a greater range and prominent positioning of fruit and vegetables improves women’s fresh fruit and vegetable purchasing and their own and young children’s diets.

Public health benefits: This study is politically and scientifically important. Study findings will be of interest to the public, researchers, food retailers and the government. The results could be used by the government or supermarkets to create in-store layouts that prompt customers to buy healthy foods. Healthier layouts in supermarkets could help everyone to eat better, not just those who are interested in healthy eating, helping people to have a healthy weight and be less likely to develop diabetes or heart disease.

For more information, you can contact WRAPPED Principal Investigator Dr Christina Vogel, Co-Principal Investigator Prof Janis Baird or a member of the WRAPPED study team:
Email: wrapped@soton.ac.uk    Freephone: 08001692042    Text WRAPPED to 66777