Food pictures dominate the front of packaging. Such pictures often implicitly suggest what should be an appropriate portion size. The current work focuses on the prevalence and potential effects of these implicit serving size suggestions on serving cereal.
The U.S. Food and Drug Administration (FDA) has focused regulation of serving size suggestions on the suggested serving size that are verbally stated on nutrition panels. However, serving sizes depicted on packaging may offer a more salient and powerful guide to consumption than that offered by verbally suggested serving size on nutrition labels. If depicted portion sizes are greater than suggested serving size printed on panels, they may implicitly suggest a larger consumption norm, and consequently a greater serving size. Consumers may unwittingly be primed by such suggestions to serve greater portions. Given its potential impact on consumption, such influence has implications for public policy, company practice, and consumer welfare.
Consumption norms, ideas of what quantity is appropriate for consumption, have steadily increased over the years . As portion sizes have increased, so has energy intake, leading to increases in obesity rates, and concomitant health problems [2–7].
Suggested serving sizes are one means whereby consumers may determine the appropriate consumption amount . However, a variety of other, potentially more powerful, elements in the food consumption environment can guide food consumption by signaling appropriate consumption amounts [9, 10]. For example, larger dishes can signal that one should consume more, and may consequently lead to increased eating [11, 12]. Such elements in the environment serve as implicit consumption norms - suggestions of appropriate consumption sizes that are implied rather than being explicitly and verbally stated (as on nutrition labels) .
Product packaging in particular can cue consumers to consumption norms. Traditionally, the focus of research regarding portion sizes and packaging has been on explicitly suggested serving sizes. While the correct use of nutrition panels can indeed help consumers make healthier food choices [13, 14], and determine the correct portion size in particular, the impact of labels on consumption is negligible [13, 15–17]. Many consumer segments ignore labeling information, and do not use nutrition facts panels in making their decisions [18–20].
Suggested serving size in particular may be ignored by many consumers . Even when attention to suggested serving size is heightened, consumers may not apply the suggestions correctly . Consumers generally have difficulty translating suggested serving sizes into action . In particular, consumers may have difficulty understanding the units used in suggested portion size .
Visualization may play an important role in the usefulness suggested serving sizes . However, consumer may have difficulty visualizing portion sizes. For example, they may not have a clear idea on how to visualize “30 g” of food such as breakfast cereal . Given that food serving is visually guided, the lack of easily visualizable suggested serving sizes limit their effectiveness . Visual guides may in this sense be more effective guides to consumption.
Due to their limitations, nutrition labels’ impact on changing health behavior has come into question . Research findings demonstrating their lack of effectiveness has contributed to this [15, 16, 18–20]. For example, in a recent study examining the efficacy of labels in informing consumers about calories contained in products, only 54.2% of participants correctly estimated the number of calories in a Coke bottle, even after examining the label .
Further, verbally stated suggested serving sizes may be suspect due to company motivations. Companies may be motivated to offer serving sizes that are lower than what consumers would actually consume, because displaying lower serving sizes makes a product appear lower calorie, at least within the current labeling system in the US. This, in turn, leads to increased product choice .
Visual elements of product packaging, such as package size, can serve as implicit consumption norm cues and lead to increases in consumption [2, 28–30]. For example, 100-calorie packs have been shown to lead to reduced consumption [31, 32]. Similarly, just labeling a product as large or small can cue appropriate consumption amounts . Visuals in general are potent at influencing consumption . For example, a visual cue to appropriate portion size in the form of a visual, colored “marker” can signal the appropriate time to stop consumption .
The current work focuses on the influence of product imagery on packages, and specifically depicted serving sizes, on consumption. Unlike text, the images on packaging may stand out and capture consumers’ attention . In general, the visuals on a package may exert a more dominant influence than words . They encourage increased engagement, and can in turn play a central role in consumer decisions [37–41].
Packaging in general has been shown to have extensive influence on product judgment . In the cereal domain specifically, companies have been shown to employ a variety of means to reach consumers, particularly children . Packaging can generate increased product liking and increase purchases [44, 45]. Product images on packaging, in particular, provide marketers with a means of communication and persuasion .
The images on packaging are potent at influencing consumers, and children in particular [41, 46]. Given the extent to which children are influenced by imagery, images on food packaging have been shown to have an influence on consumption . For both children and adults, the photographs and graphics on a package can provide a guide to consumption norms, how much one might believe is reasonable and appropriate to serve [8, 36]. This is particularly true given the importance of visualization to the determination of serving size . If an exaggerated depicted portion suggests an exaggerated consumption norm, this may translate to increased serving, which would in turn contribute to overeating [6, 7, 12, 48, 49].
Importantly, depicted portion size may even exert an influence on children that are too young to process verbal information and so may be particularly vulnerable to visual presentation. Children may not read nutrition labels, but are able to estimate serving size based on pictures, and so may be influenced by depicted serving size .
Though images offer a potent channel whereby to cue appropriate consumption amounts, research on the use of such visual guides to serving sizes is notably sparse. The current studies aimed to examine whether depicted portion size may indeed affect a meaningful effect on amounts served.
Although exaggerations of depicted portion sizes occur across a wide range of products, the focus of the current paper will be on breakfast cereals, since they are frequently and widely consumed, given that their packaging clearly illustrates individual serving size (i.e., one bowl), and since they are particularly relevant for and marketed to children, which constitute a vulnerable population in formative stages of consumption habits [41, 43, 51].
The first study aimed to document deviations of depicted serving size from serving size suggested on nutrition panels. Study 2 next examined if the quantity consumers served was influenced by depicted serving size.