Food taxes and calories purchased in the virtual supermarket: a preliminary study

Purpose
The purpose of this paper is to examine the effectiveness of three food taxation schemes on energy (kcal), saturated fat (gram) and sugar (gram) purchased in the virtual supermarket.

Design/methodology/approach
Based on the literature, three food taxation schemes were developed (sugar tax, saturated fat tax and a nutrient profiling tax) and implemented in the three-dimensional virtual supermarket. A randomized control trial was conducted to determine the differences in the amount of energy (kcal), saturated fat (gram) and sugar (gram) purchased for a one-week food basket.

Findings
In total, 191 Dutch adults were randomly assigned to a sugar-tax condition (n=48), a saturated fat-tax condition (n=37), a nutrient profiling-tax condition (n=62) and a control (no-tax) condition (n=44). Fully adjusted models indicated that compared to the no-tax condition, no significant effects of a sugar-tax condition (B: −2,041 kcal (95% CI −5,350 to 1,914)), saturated fat-tax condition (B: −2,717 kcal (95% CI −6,596 to 1,163)) or nutrient profiling-tax condition (B: −1,124 kcal (95% CI −4,538 to 2,292)) were found on the amount of energy purchased. Also, none of the taxation schemes showed significant effects on saturated fat or sugar purchased.

Originality/value
This is one of the first randomized controlled trials testing the effectiveness of a variety of food taxes in the virtual supermarket. This preliminary study provides important directions for future research (the design, results, as well as the lessons learned with respect to recruitment, incentives and technology).