When do digital calorie counters reduce numeracy bias in grocery shopping? Evidence from an online experiment

Purpose: Numeracy skills hinder a consumer’s ability to meet nutrition and calorie consumption guidelines. This study extends the literature on nutritional labelling by investigating how a calorie counter, which displays the total amount of calories consumers add to a shopping basket, aids them in making food choices. It aims to ascertain whether the calorie counter affects food choices and also how individual and situational factors moderate this effect.

Design/methodology/approach: To test the developed hypotheses, we designed an online shopping experiment and administered it to a national panel of British consumers. This included a sub-sample from the general population who did not report any food related health conditions (n=480) and a separate sub-sample from the same population who had reported a food related health condition, or lived with someone who had one (n=250).

Findings: The results show that the calorie counter leads to a large and statistically significant reduction in calories purchased when compared to the no nutritional information condition, and a small (but statistically insignificant) reduction in the number of calories chosen by consumers when compared to the nutritional information only condition. The main effect is moderated by individual factors such as whether or not the person has a health condition, and shopping situations which involve time pressure.

Research implications: Although the main effect of the calorie counter was not statistically significant when compared to the nutrition information only condition, the effect was in the correct direction and was statistically significant for consumers who had a food related health condition. Our conceptualization and findings are largely consistent with Moorman’s (1990) nutrition information utilization process, but also suggest that situational factors should be considered when understanding nutrition information processing.

Practical Implications: The findings from this study provide the first evidence to suggest that aggregating calorie information through a calorie counter can be a useful way to overcome consumer numeracy biases, particularly for those with existing health conditions and who are most motivated to use nutritional information. Based on the descriptive statistics the main effect was comparable to the UK’s sugar tax in its impact and we estimate this would lead to a reduction in calories consumed of about 5000 per year, even for consumers who did not report a health condition. Further testing is required with different formats but these results are encouraging and are worthy of further research.

Originality/value: This is the first study to investigate how consumers react to aggregated nutritional information for a basket of products, mimicking a real shopping situation. Such information has the potential to become more relevant and useful to consumers in the context of their overall diets. As technology advances rapidly there is a need to explore alternative ways of presenting nutritional information so it connects more easily with consumers. These results point very much to a more targeted and personally relevant approach to information provision, in contrast to existing mass communications approaches.