The effect of menu labeling with calories and exercise equivalents on food selection and consumption

Point-of-purchase menu labeling, particularly at fast food restaurants, has been of special interest in the fight against obesity. As fast food consumption has been correlated with obesity and other negative health outcomes, these food outlets are being targeted for change. In 2010, the US federal health care reform bill was signed into law and includes a requirement that restaurant chains with at least 20 outlets nationwide post calorie labels on menu boards [1]. It has been suggested that knowledge of the calories contained in foods is essential to choosing and consuming an energy-balanced diet [2],[3]. While consumer polls show a desire for calorie information at the point-of-purchase in restaurants [4], research on the actual effects has shown mixed results [5]-[7].

One possible reason for inconsistent effectiveness may be the lack of understanding of the value of a calorie or the lack of a reference amount for a calorie [8],[9]. Exercise equivalents have been discussed by nutrition experts as a potential method to inform consumers about calorie values [10]. Exercise equivalents are defined as the amount of time doing particular physical activities that would be needed to burn off calories in foods. For example, burning off a 300-calorie hamburger would require about 75 minutes of walking, after expending the calories needed for daily subsistence. Exercise equivalents could potentially simplify food and/or restaurant nutrition labels, increase understanding of calories and of energy imbalance, and facilitate a decrease in overall energy intake [11].

Literature exploring the use of exercise equivalents is limited. A new study by Dowray et al., explored the potential effect of exercise equivalents on menu labels. This study was a web-based survey, and asked participants to “imagine they are in a fast food restaurant”, and order a meal from an online menu. Participants were randomly assigned to see one of four menus (calories only, calories and number of minutes to walk to burn off that amount of calories, calories and number of miles to walk off that amount of calories, or no information). The results from this study are significant; calories were significantly different based on menu type (p = 0.02), with the calories and exercise equivalents in mileage group ordering significantly less calories than the other three groups (p = 0.0007). Additionally, 82% of their participants reported a preference for exercise equivalents on menu labeling [12]. This study shows a positive impact in using exercise equivalents to aid in the understanding of a calorie, and potential to help consumers order lower calorie food items. These findings are consistent with an earlier study, which showed that exercise equivalents helped reduce purchases of sugar-sweetened beverages among low-income black adolescents [11].

A study by Fitch et al. assessed the influence of calorie information versus exercise equivalents on food selection amongst adolescents and adults who ate at fast food restaurants regularly [13]. This study indicated that calorie labels were preferred to exercise equivalents overall (71%), and some cited the latter as demotivating [14]; however, the Fitch study has limitations. They tested the impression of exercise equivalents rather than their actual effect, examined exercise equivalents as an alternative to, rather than addition to calories, and had a predominantly white sample population, many of whom were not overweight or obese. They also found that exercise equivalents had a more favorable impression among non-whites than whites, and, along with another study [14], among younger persons.

The current study aimed to test the actual effect of exercise equivalents on fast food point-of-purchase behaviors. Research has shown that non-white, overweight and obese individuals are more likely to consume fast food and thus be at increased risk of negative health outcomes [15]. For this reason, we recruited young, predominantly non-white overweight and obese women for our study and presented them with exercise equivalents alongside calories at the point-of-choice. We compared the effect of the exercise equivalents with the provision of simple caloric information or no information at all. Additionally, we sought to evaluate the impact of restrained eating on point of purchase and consumption behaviors.

The current study was a pilot. While the researchers acknowledge the small sample size as a limitation, the goal of the study was to test a new design: the potential use of exercise equivalents for public health outreach, with hopes that other researchers can utilize for future studies on this topic. Thinking of new ways to promote healthy behaviors at the point-of-purchase is important for nutrition researchers, educators, and policymakers. We believe the novelty of our experimental design, with emphasis on using exercise equivalents as a nutrition intervention for at risk individuals, furthers thought on point-of-purchase interventions.

In all study groups, both restrained and unrestrained eaters had an average decrease in number of calories ordered from Lunch 1 to Lunch 2, with the exception of restrained eaters in the group receiving no calorie or exercise equivalent information at Lunch 2. The greatest proportionate decrease in calories ordered was seen in restrained eaters in the calories-only group (24.7% decrease; p = 0.05). Unrestrained eaters in the calories and exercise equivalents group ordered an average of 275 fewer calories at Lunch 2 compared with Lunch 1, with a proportionate decrease of 14.0%, although this was not statistically significant (p = 0.24). Unrestrained eaters in the calories and exercise equivalents group had greater absolute and proportionate decreases in calories ordered from Lunch 1 to Lunch 2 than unrestrained eaters in the other two study groups. Additional analyses examining number of items ordered revealed no significant differences by study group (data not shown).

During the exit questionnaire, 57 participants (92%) said they believed that a combination of calories and exercise equivalents would influence the foods they ordered at a fast food restaurant.

Consumption of fast foods is common in the US [20]. To reduce negative effects and mitigate public health disparities in food environments, interventions may be especially critical in populations of persons who eat at fast food restaurants [21]. Calorie information presented at point-of-purchase is a relatively new concept nationwide; however, research has shown mixed results at the point of purchase. There is a potential for exercise equivalents as a supplemental guide to novice calorie counters and those unaware of the negative health implications in consuming fast food.

While the current study was underpowered, we believe the novelty of the design of the experiment, the emphasis on utilizing exercise equivalents for a potential nutrition intervention for at risk individuals, will heighten awareness for future researchers on the need for further investigating point of purchase interventions, specifically exercise equivalents. There have been several real-world studies that have shown an impact on calories ordered using sales data. For example, using a randomization design, Roberto et al. reported that calorie information on restaurant menu did reduce the total amount of calories people ordered and consumed [22]. Another quasi-experimental design study [23] examined the sales data before and after provision of point-of-selection nutrition labels found that the nutrition labels reduced average energy content of entrée purchased without reducing overall sales. Additionally, using data from Starbucks, Bollinger et al. found that mandatory calorie posting in chain restaurants resulted in 6% decrease in calories per transaction [24]. Dumanovsky et al. conducted a cross-sectional survey and assessed consumer purchases in 2007, before caloric information was mandated by chain restaurants, and again in 2009, after the menu labeling legislation was passed. Although they did not find an overall change in calories consumed, they did observe a significant decrease in the calories consumed at specific chain restaurants including McDonald’s, Au Bon Pain and KFC [25].

With the rollout of the new law mandating fast food restaurants list caloric value for all menu items pending, understanding the potential implications is important. Calorie information at the point-of-purchase for restaurants has been required by law for chain restaurants in New York City since 2008 [26], in California, Oregon and Maine since 2009 [27] and has also been adopted in many other cities and counties [28].

A recent study by Krieger et al. is one of the first to investigate the effect of the nationwide menu labeling bill. This cross-sectional study surveyed fast food patrons both before the menu label regulation was implemented, and again 18 months later, post-regulation. Interestingly, they found a significant decrease in calories ordered in coffee and taco establishments, but not in burger and sandwich shops; and a decrease in calories ordered by women, but not men [29].

The effectiveness of nutrition labels on point-of-choice food purchasing has provided mixed results. Similar to the present study, prior studies that have looked at point-of-purchase at fast food restaurants and the other at nutrition labels have also failed to show statistical significance [30],[31]. This study provided a real-world setting was created to measure actual point-of-purchase behavior [32]-[34]. The unique strength of this study is that the study design provides a potential alternative or addition to the soon-to-be implemented national menu labeling law as a public health intervention. This study illustrates a novel design to test the effectiveness of adding exercise equivalents to provide a frame of reference for consumers. Using exercise equivalents on food labels and food served away from home could provide consumers with a context for the term, “calorie”, [11] and, thus, contribute to the understanding of the nutrition labels for better food choice and selection.

Presentation of caloric information of fast food translated into exercise equivalents did not have a statistically significant impact on the food choices of overweight and obese women who were restrained eaters or unrestrained eaters. However, unrestrained eaters presented with calorie information and exercise equivalents combined had a larger decrease in calories ordered compared to those with calorie information only and for those with no information. The impact of calorie information with exercise equivalents on unrestrained eaters should be further examined as unrestrained eaters generally do not deliberately attempt to limit their food intake [17].

There are several limitations in this exploratory study. The small study sample size is a major limitation of this study. Additionally, the study was limited to female college students thus limiting its generalizability. Another limitation is that individuals were getting food at no cost, which might have influenced the total number of food items, and hence amount of calories chosen [30]. The average calories for the foods chosen for Lunch 1 and Lunch 2 were 1215.16 and 1087.50, respectively. Dumanovsky and colleagues (2009) established baseline data on mean calorie intake at Burger King of 926.2. Participants in the current study chose approximately 225 more calories per meal on average than participants in Dumanovsky study, perhaps because the food was free [31]. This study did not collect pre- and post-intervention food diaries. It is possible that participants who chose lower calorie foods during the intervention may have increased their intake later in the day to compensate.

Additionally, there is a potential limitation in using exercise equivalents, or calories alone, to promote lower calorie food choices as opposed to nutritionally dense options. Lower calorie foods do not necessarily make a food nutritionally “better” than another. Despite this, although nutritionally and calorically dense foods such as tree nuts, avocado, and fatty fish are touted as an important part of a healthful diet, they are not commonly offered at fast food restaurants. As such, exercise equivalents and calories listed can potentially provide meaningful reference points for fast-food patrons [32].

The current study presented an intervention designed to improve the effectiveness of calorie information on point-of-choice. The concept of menu labeling, exercise equivalents and other point-of-purchase messages are a potentially useful way to reach consumers at the point of their food decision. This research, combined with previous studies, suggest that in addition to calorie labeling information, there is a need for further research of point-of-purchase interventions [34] to find the most effective ways of presenting the menu labels for general public. Although this study was not powered to see statistical differences, the concept that behaviors may differ based on calorie and exercise information should be further explored in a larger study.