Overall, positive associations were found between exposure to fast food marketing and fast food brand preferences and intake. Preference for specific fast food brands was generally highest across countries when exposed to general fast food marketing ≥ 2x/week and ≤ 1x/week compared to those who were not exposed, and also higher among those who self-reported exposure to marketing for each respective brand compared to those who did not, and this relationship was consistent across all countries. In terms of fast food intake, reported consumption was generally highest across countries when exposed to general fast food marketing ≥ 2x/week and ≤ 1x/week compared to those who were not exposed. Across almost all countries, reported consumption of fast food was higher amongst those who were exposed to marketing for McDonald’s, KFC and Subway as opposed to those who were not. With respect to sociodemographic characteristics, across most countries overall, respondents who identified as a minority ethnicity were more likely to consume fast food than those of a majority ethnicity, and females were less likely to reportedly consume fast food than males.
The study findings suggest that the likelihood of preferring a fast food brand and consuming fast food increased with both exposure to brand specific and general fast food marketing. These findings are consistent with previous epidemiological evidence assessing the association between food marketing that is not food category specific and health behaviours including youth’s intake and preferences, and also consistent with similarly designed cross-sectional observational studies among adults and younger age groups and specific food categories.43,58−65 Our findings build on this current body of knowledge by providing evidence for these associations for fast food specifically, which is important since it is the most marketed of all food categories.19,22,26,30,33 This study also found that the odds of preferring a brand were higher overall across models when variables included recall of brand-specific fast food marketing, as opposed to more general exposure to fast food marketing. This may indicate that fast food brand-specific marketing has a greater effect on youth’s preferences for the respective brand compared to general fast food marketing, which would be consistent with data from other fields of research investigating the association between cigarette brand-specific marketing and brand preferences amongst adolescents and young adults.66,67 This stronger association may also be due to improved recall of instances of brand-specific marketing (compared to general instances of fast food marketing), as well as the type of questions asked (e.g., brand-specific marketing exposure was measured using a response of “yes” or “no”, compared to general marketing exposure which was assessed using a 6-item Likert scale). To help address this, the 6-item scale was re-categorized into a 3-item scale, but the associations amongst the brand-specific measure remained stronger. Although the results were largely consistent across countries, we cannot fully conclude from this study alone that these associations are causal, due to the self-reported, cross-sectional nature of the data. For example, the association between marketing exposure and food intake could be bidirectional in nature: it is possible that greater intake of certain fast food brands may also lead to increased exposure/attention to brand-specific marketing. However, our results are supported by existing epidemiological data and will also help to strengthen existing associations between exposure to unhealthy food marketing and increased preference and consumption.68
Overall, the country-stratified results were fairly consistent across countries. As mentioned previously, the policy environments restricting unhealthy food marketing to children differ in stringency across the countries investigated, but yet, exposures are still high and the relationships between these exposures and eating behaviours are consistently strong across countries. Although most existing policies apply to children under the age of 13 and this study investigated those 10–17 years old, these findings still indicate that fast food marketing exposure is affecting the eating behaviours of youth and that current regulatory policies need to be strengthened.
This comprehensive survey also allowed for exploration of sociodemographic differences within the measured associations. Overall, females in most countries were less likely to report consumption of fast food than males, which is congruent with previous research measuring fast food intake.70–72 An explanation for this consistent finding could be that female youth are more likely to engage in diet-related practices and are more attentive to their body image.73,74 It may also be possible that males are targeted by industry marketing practices more often than females, as males are reportedly featured more frequently in food marketing, which could lead to greater persuasion towards consuming the product.75 We also found that individuals classified as ethnic minorities were more likely to report the consumption of fast food than ethnic majorities. Recent data has suggested that Black and Hispanic youth in the US are being disproportionally exposed to more unhealthy food marketing, which brings concern as socioeconomic status is associated with ethnic minority status in countries like the US, and those with a lower socioeconomic status are more likely to exhibit poorer health outcomes.76–83 Thus, the marketing unhealthy foods may be exacerbating poor health outcomes in already at-risk populations. Implementing stringent regulations to protect youth from exposure to unhealthy food marketing may help to reduce these differences.78
Strengths And Limitations
To our knowledge, this is the first study to examine associations between specific fast food brand marketing exposure and youth-reported intake and preferences. This study employs consistent measures across a large sample size with a wide age range and includes respondents from a variety of ethnicities and socioeconomic backgrounds in six different countries, which allows for greater generalizability and between country comparisons. Post-stratification weights were also used to provide a more representative sample, which also increases generalizability of our findings. Additionally, as the exposure measures did not specifically focus on marketing in particular media, this allowed us to report our associations based on a wide range of exposures.
Interpretation of the findings should consider potential limitations of self-reported data. In addition to being subject to recall bias and reverse causation, the self-reported exposure variables do not take into account the power, ad content, frequency, and extent to which it targets the individual. Past research has shown that certain marketing techniques affect’s one’s recall of the advertisement, which could have altered their ability to remember marketing exposures.69 The self-reported fast food intake variable is also subject to recall bias and has its own limitations, as it measures intake from a few settings (i.e., restaurants, food stands or vending machines) in addition to fast food places. However, we would argue that food from restaurants, food stands and vending machines can also be considered fast food, due to the ease of purchase and poor nutrient content of most foods sold from these sources. Aside from its limitations, self-reported measures are also valuable in that they are more feasible to collect. Objective measures are often more difficult to gather, as they are more resource-intense and do not accurately represent day-to-day choices.68 Nevertheless, existing evidence suggests that self-reported exposure measures are correlated with objective exposure measures.86,87 The increased feasibility of self-reported measures also allows for more frequent monitoring and the ability to collect and compare data across multiple countries simultaneously.
Additionally, it is possible that what respondents encompassed under ‘fast food advertising’ may have been interpreted differently by individuals, introducing additional bias. This study is also subject to survey research limitations, as recruitment was completed using nonprobability-based sampling, meaning these findings may not be representative of national estimates. To address this to an extent, data were weighted by age group, sex, region, and ethnicity (except in Canada), but this did not completely remove the effect.