This study presents different ways of presenting information on food calories and assesses how useful consumers find them. It showed participants of 3 groups the calorie content of a ham sandwich, displaying this information in different formats as shown in the diagram below.
Note that the research was a qualitative study and involved relatively few participants (38 people) all of which had adequate ‘nutritional literacy’ (unlike 50% of the US population) so the findings are not generalisable. This said, the findings do suggest that displaying physical-activity-equivalent information in addition to calories holds promise and may be worth exploring further. Walking tends to be more meaningful to people than other activities such as running or swimming. However there was a lot of focus group discussion as to its applicability to the individual – i.e. the energy time/distance required to expend the calories was based on a 160 pound person running or walking at a specified rate/minute. Heavier/lighter and faster/slower individuals would need to walk/run/swim a different length of time.
The citation and abstract is as follows:
Swartz J J, Dowray S, Braxton D, Mihas P and Viera A J (2013). Simplifying healthful choices: a qualitative study of a physical activity based nutrition label format. Nutr J. 2013 12:72. doi: 10.1186/1475-2891-12-72.
Background: This study used focus groups to pilot and evaluate a new nutrition label format and refine the label design. Physical activity equivalent labels present calorie information in terms of the amount of physical activity that would be required to expend the calories in a specified food item.
Methods: Three focus groups with a total of twenty participants discussed food choices and nutrition labeling. They provided information on comprehension, usability and acceptability of the label. A systematic coding process was used to apply descriptive codes to the data and to identify emerging themes and attitudes.
Results: Participants in all three groups were able to comprehend the label format. Discussion about label format focused on issues including gender of the depicted figure, physical fitness of the figure, preference for walking or running labels, and preference for information in miles or minutes. Feedback from earlier focus groups was used to refine the labels in an iterative process.
Conclusions: In contrast to calorie labels, participants shown physical activity labels asked and answered, "How does this label apply to me?" This shift toward personalized understanding may indicate that physical activity labels offer an advantage over currently available nutrition labels.
You can download it here.
An article covering the research can be found here.
Clearly this is a health focused study but it’s interesting in relation to carbon labelling (see here). One of the main problems with carbon labels as it stands is that a. people are not very interested in the carbon footprint of the food they eat and products they use and b. they don’t have a sense of what 50g CO2eq, for example, actually means. As regards the latter, this potentially can be overcome by relating the carbon emissions to something that people can understand, such as miles driven in a car.
Ultimately of course the goal might be to combine nutritional and environmental information. This raises questions about a. the selection of metrics to use (eg. just CO2e emissions, or also metrics covering impacts on water or biodiversity?) and b. the risk of confusing/alienating people with too much information.