The effect of presenting relative calorie information on calories ordered

In this research, we tested the effect of a novel method of presenting calorie information-highlighting relative differences in calories among ingredients. We conducted an online hypothetical food choice experiment where 633 participants selected the ingredients for a sandwich from five categories: meat/protein, cheese, spread/dressing, bread, and vegetables. Each participant was randomly assigned to one of four calorie information conditions: 1) a condition in which no information about calories was provided, 2) a condition in which calorie information was provided for each ingredient, 3) a condition in which calorie information was presented relative to the highest calorie item, and 4) a condition in which calorie information was presented relative to the lowest calorie item. Participants in the high- and low-calorie reference conditions ordered between 32 and 36 fewer calories per sandwich than participants in the no-calorie information control condition (p ≤ 0.04). Calories ordered by participants in the per-item calorie condition were not significantly different than the control. Presenting relative calorie or other nutritional information to make health-related trade-offs more salient may guide consumers to make healthier choices.