Objective: To assess how well supermarket sales data from a major supermarket chain can reflect on regional differences in dietary behaviour by comparing the sales data with the results provided by the annual health behaviour surveys. Design: Cross-sectional observational study.

To test the feasibility of the use of supermarket sales data in evaluating a local point of purchase intervention and to assess the impact of the intervention six and 12 months later. Staged point of purchase intervention pilot study followed by a longitudinal observational study. The study was carried out in one supermarket in Mikkeli, Finland. Foods were classified as healthier or reference products based on their labelled content of salt and saturated fat. The sales of packaged foods containing reduced amounts of salt and/or saturated fat were promoted with a stepwise increasing intervention culminating in a``heart week''. In addition all unplanned promotional activities during the intervention were surveyed. Information on the sales of both the promoted products and reference products was collected daily from the supermarket's computer system. Direct and proportional sales of both single products and whole food groups were analysed during the intervention and at follow-up. In addition the supermarket environment and the supermarket's advertising in the local newspaper were checked. Short-term variations in the sales could be seen related to the promotion activities. During the heart week the sales of actively promoted healthier products increased by 37-49 per cent. Variations in the sales of reference products could also be seen; the proportional sales of some healthier products declined significantly when the reference products were actively promoted. The supermarket environment was still affected by the intervention at both follow-ups. The mean percentage salt content of the weekly sales had declined in all food groups and the mean percentage fat content had either declined or remained unchanged. Computerised sales data provide a useful and rapid means of evaluating supermarket based interventions. The intervention had an impact on the supermarket environment which was visible at follow-up.

Proportional sales data are proposed as a tool for measuring the effect of nutrition interventions and also as a possible indirect assessment for population salt and fat intake.

The aim of the study was to assess the extent to which lightly salted food products are included in the assortments of Finnish supermarkets and prominently placed on shelves. The study was carried out in eastern Finland in four supermarkets of different food chains. Six food groups of importance for people's salt intake were considered. The food labels of 689 packaged food products were checked for salt and sodium information on the basis of Finnish regulations on salt. Products with reduced salt contents were found in most food groups but not among whole-meat or ready-to-eat foods. Half of the products with reduced amounts of salt were labelled "lightly salted". All four supermarkets had a similar assortment of lightly salted products. From the public health point of view, the food industry should increase the supply of lightly salted products, and make a special effort to develop lightly salted ready-to-eat foods.

Supermarkets are potential sites for collaboration between the health sector, food industry and the sales business in health promotion work. In order to establish the possibility of co‐operation between the municipal food control authority and the retail stores, an intervention project was started in one supermarket in Finland. The aim of the project was to encourage the supermarket to take health aspects, especially related to salt and saturated fat, into consideration in their marketing and to find out how the customers react to this project. The intervention was designed as a step‐wise programme with gradually increasing intervention. During the intervention period 600 customers were interviewed. The awareness of the campaign rose steadily up to over 50 percent during the last phase. The reporting of the local newspaper and radio seemed particularly to increase the customers’ awareness. Both the customers and the supermarket workers had a very positive attitude towards the project throughout the intervention. The direct impact of the intervention on reported purchase behaviour was small but the study showed that health promotion work in co‐operation between food control and supermarkets does work. The project could serve as a model for similar larger health promotion projects and might inspire other supermarkets to help their customers make healthier choices.