- Open access
- Published: 27 July 2023
The impact of fast food marketing on brand preferences and fast food intake of youth aged 10–17 across six countries
- Mariangela Bagnato 1 ,
- Marie-Hélène Roy-Gagnon 1 ,
- Lana Vanderlee 2 ,
- Christine White 3 ,
- David Hammond 3 &
- Monique Potvin Kent 1
BMC Public Health volume 23 , Article number: 1436 ( 2023 ) Cite this article
Consumption of fast food, which is associated with poor diet, weight gain and the development of noncommunicable diseases, is high amongst youth. Fast food marketing, a modifiable determinant of excess weight and obesity, affects youth’s food-related behaviours. This study aimed to examine the relationship between exposure to fast food marketing and the fast food brand preferences and intake amongst youth aged 10–17 across six countries.
Data from 9,695 youth respondents living in Australia, Canada, Chile, Mexico, the United Kingdom (UK) and the United States (US) were analyzed from the 2019 International Food Policy Study (IFPS) Youth Survey. Survey measures assessed exposure to fast food marketing and brand-specific marketing, and preference for these brands and fast food intake. Regression models adjusted for age, sex, income adequacy and ethnicity were used to examine the associations.
Exposure to fast food marketing was positively associated with brand preferences and intake consistently across most countries. Overall, preference for McDonald’s (OR:1.97; 95% CI:1.52, 2.56), KFC (OR:1.61; 95% CI:1.24, 2.09) and Subway (OR:1.73; 95% CI:1.34, 2.24) were highest when exposed to general fast food marketing ≥ 2x/week compared to never. Preference for McDonald’s (OR:2.32; 95% CI:1.92, 2.79), KFC (OR:2.28; 95% CI:1.95, 2.68) and Subway (OR:2.75; 95% CI:2.32, 3.27) were also higher when exposed to marketing for each brand compared to not. Fast food intake was highest in Chile (IRR:1.90; 95% CI:1.45, 2.48), the UK (IRR:1.40; 95% CI:1.20, 1.63), Canada (IRR:1.32; 95% CI:1.19, 1.48), Mexico (IRR:1.26; 95% CI:1.05, 1.53) and the US (IRR:1.21; 95% CI:1.05, 1.41) when exposed to general fast food marketing ≥ 2x/week compared to never and was higher across most countries when exposed to brand-specific marketing compared to not. Respondents classified as ethnic minorities were more likely to report consuming fast food than ethnic majorities, and females were less likely to report consuming fast food than males.
Exposure to fast food marketing is consistently and positively associated with brand preferences and fast food intake in all six countries. Our results highlight the need for strict government regulation to reduce exposure of unhealthy food marketing to youth in all six countries.
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The burden caused by noncommunicable diseases (NCDs), such as cardiovascular disease, cancer and diabetes, is on the rise globally. In 2019, 20% of adolescent deaths worldwide occurred as a result of NCDs and it has been estimated that 70% of premature deaths in adults are linked to behaviours that developed during childhood and adolescence [ 1 ]. Diet, physical activity and lifestyle factors are modifiable precursors to obesity and excess weight that are an ongoing threat to health and the development of NCDs internationally [ 2 ]. Between 1975 and 2016, the prevalence of obesity and overweight amongst children and adolescents between the ages of 5 and 19 worldwide increased from 4 to 18%, alongside the intake of ultra-processed foods, high in sugar, saturated fats and sodium amongst youth [ 3 , 4 ]. In Canada, youth aged 2–18 years consume over 50% of their total daily energy from ultra-processed food, elevating short- and long-term risks to health, including excess weight and obesity, mortality, and the development of noncommunicable diseases [ 5 , 6 ].
Fast food accounts for a large share of food consumed by youth as on average, over 15% of daily calories consumed by North American youth come from such foods [ 7 , 8 ]. Due to the poor nutrient quality of fast food, intake of these foods is associated with poor dietary quality and weight gain, and may compromise nutrient requirements necessary for proper growth [ 9 , 10 ].
The food environment has been recognized as a determinant of obesity and the marketing of unhealthy foods and beverages to children has been identified as a cause of poor diet and excess weight in youth [ 11 , 12 , 13 ]. Youth are valuable advertising targets for the food and beverage industry, as promoting sales in this highly impressionable age group may help to create life-long brand loyalty [ 14 , 15 , 16 , 17 ]. Youth are exposed to food and beverage marketing (herein referred to as food marketing) daily in a variety of media and settings, which have the power to influence consumption and future health outcomes [ 10 , 11 , 12 , 13 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 ]. Research from high-income countries found that the majority of advertisements on youth-oriented media promote unhealthy products and fast food in particular accounts for the largest exposure [ 19 , 23 , 26 , 27 , 28 , 29 , 30 , 31 , 32 ]. Expenditure data also shows that expenditures on youth-oriented advertising across all media is high and overall, the majority of advertising spend is devoted to unhealthy products, with fast food advertising dominating expenditures [ 22 , 33 ]. This emphasis on fast food marketing is notable as youth spend a lot of time viewing various media and hold autonomous buying power [ 14 , 15 , 16 , 17 ]. In response to the ongoing concern caused by industry marketing practices and its negative impacts on youth health, in 2010, the World Health Organization recommended that its members develop restrictions to limit the marketing of foods high in fats, sugars and sodium (HFSS) to children [ 34 ]. Globally, food marketing restrictions are either non-existent, self-regulated by the food and beverage and/or advertising industries (e.g., Canada [excluding Quebec], Australia and the United States [ 35 , 36 , 37 , 38 ]) or government regulated (e.g., United Kingdom, Chile and Mexico [ 39 , 40 , 41 ]).
The logic model of unhealthy food promotion effects predicts that preferences and consumption of unhealthy foods are direct effects of food marketing exposure that eventually lead to long-term post consumption effects such as weight gain and diet-related disease, warranting investigation into its influence on youth [ 42 ]. Currently, research evaluating the impact of unhealthy food marketing on preferences and intake of youth globally is limited, as the few studies identified do not investigate more than one country, are focused on exposure from a specific media channel (mostly television), use a wide variety of data collection methods, rely on data collected from parents, and/or have a narrow age range and small sample size [ 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 ].
No previous studies have tested the association between youth’s self-reported exposure to and preference for specific fast food brands, nor does any investigate fast food marketing exposure, fast food restaurant brand preferences and fast food intake in this population simultaneously. Given that fast food is the most marketed food category to youth across most media [ 19 , 22 , 26 , 30 , 33 ], further investigation of its effects on youth is warranted. The purpose of this study was to examine the relationship between exposure to fast food marketing and the fast food brand preferences and intake of youth in six upper and middle income countries and to explore the relationship between sociodemographic characteristics and fast food preferences and intake.
Data were from the 2019 International Food Policy Study (IFPS) Youth Survey, an annual repeat cross-sectional survey conducted in six countries: Australia, Canada, Chile, Mexico, UK and the US. Data were collected via self-completed web-based surveys conducted in November–December 2019 with youth aged 10–17 years. Respondents were recruited through parents/guardians enrolled in the Nielsen Consumer Insights Global Panel and their partners’ panels and invitation links were sent to panelists within each country. Those who confirmed they had a child aged 10–17 living in their household were asked for permission for their child to complete the survey, with quotas for age and sex groups in the UK and US. After eligibility screening, all potential respondents were provided with information about the study and asked to provide assent. Surveys were conducted in English in Australia and the UK; Spanish in Chile and Mexico; English or French in Canada; and English or Spanish in the US. Members of the research team who were native speakers in each language reviewed the French and Spanish translations independently. Brand marketing exposure and preference were assessed for McDonalds, KFC and Subway as these brands are among the global leaders in fast food service and have chains in each of the 6 countries [ 56 ]. The median survey time was 24 min [ 57 ].
The child’s parent/guardian received remuneration in accordance with their panel’s usual incentive structure (e.g., points-based or monetary rewards, etc.). A full description of the study methods can be found elsewhere [ 57 ].
Independent Measures: Self-reported exposure to fast food marketing
Self-reported exposure to fast food marketing was assessed using two measures: general exposure to all instances of fast food marketing and exposure to only brand-specific fast food marketing. First, general exposure to fast food marketing was assessed using the following measure: “In the last 30 days, how often did you see or hear advertisements for these kinds of food or drinks? Ads for fast food from a restaurant”. The 6-item Likert scale for general exposure to fast food marketing was recategorized into the following: “never” (“never”), “ ≤ 1x/week” (“less than once a week”, “once a week”), and “ ≥ 2x/week” (“a few times a week”, “every day”, “more than once a day”). Second, self-reported exposure to McDonald’s, KFC and Subway marketing specifically, was assessed using the corresponding brand’s logo displayed with the following measure: “ Have you seen an advertisement for this restaurant in the last 30 days?” ( “yes”, “no”, “don’t know” or “refuse to answer” ) .
Outcome Measures: Self-reported fast-food intake and fast food brand preference
7-item emoji-based Likert scale used for the measurement of fast food brand preference
The sociodemographic measures included in this study were the respondent’s age, sex at birth, perceived income adequacy and ethnicity. Age was collected as a continuous variable. Sex at birth was collected as either “male” or “female”. Income adequacy was collected using the following measure: “ Does your family have enough money to pay for things your family needs?” (“not enough money”, “barely enough money”, “enough money”, “more than enough money”, “don’t know” or “refuse to answer”). Perceived income adequacy was recategorized into a binary variable for either “enough money” ( “enough money” and “more than enough money” ) or “not enough money” ( “not enough money” and “barely enough money” ). Ethnicity was assessed using census measures from each country and re-coded to either “majority” or “minority” to derive comparable measures across countries.
The analytic sample included 11,108 respondents. A sub-sample of 9,695 respondents were included in the current analysis after excluding those with missing and/or incomplete data (i.e., “don’t know”, “refuse to answer” or left their answer selection blank) on sociodemographic characteristics, predictor variables and outcome variables (1,413 respondents; 12.7%). Sensitivity analyses indicate that excluded respondents were not different demographically to the final analytical sample. Data were weighted with post-stratification sample weights constructed using a raking algorithm with population estimates from the census in each country based on age group, sex, region in all countries, and ethnicity (except in Canada, where ethnicity wasn’t considered in the sample weights). All estimates reported throughout are weighted. Statistical analyses were conducted using SAS Studio OnDemand for Academics (SAS Institute Inc., 2021).
Ordinal logistic or negative binomial regression models were used to model the associations as appropriate. Each model was adjusted for age, sex, perceived income adequacy and ethnicity. Statistical significance for all models was set at an alpha level < 0.05, and significance was determined using a p -value < 0.05 or a 95% confidence interval. Two-way interaction terms were tested between country and each of the sociodemographic variables. Significant interactions were noted for the associations between youth’s self-reported general exposure to fast food brand-specific marketing and self-reported fast food intake (p < 0.05), and the association between youth’s self-reported exposure to brand-specific marketing and self-reported fast food intake (p < 0.05). Since some significant interactions were found, all results were stratified by country.
Weighted sample characteristics of youth respondents aged 10–17 in all six countries are presented in Table 1 . Proportional differences in sociodemographic characteristics were noted across all countries. Overall, there was a higher proportion of adolescents aged 13–17 in all countries, the US had a higher proportion of minority respondents than other countries, and Canada had a higher proportion of respondents who perceived their family to have enough money compared to the other countries. In terms of general exposure to all fast food marketing, between 58–75% of respondents reported exposure ≥ 2x/week, with the greatest exposure reported in Mexico (75.3% of respondents) and the least exposure reported in the UK (58.7%), whereas between 17–26% of respondents reported exposure ≤ 1x/week with the greatest exposure reported in the UK (26.4%) and the least exposure reported in the US (17.3%).
Association between youth’s self-reported general exposure to all fast food marketing and fast food brand preference
General exposure to all fast food marketing and preference for mcdonald’s.
Overall, the odds of preferring McDonald’s were significantly higher in the UK and the US and significantly lower in Mexico and Chile compared to Canada (Table 2 ). In terms of general exposure to fast food marketing, overall, respondents reportedly preferred McDonald’s most when exposed to general fast food marketing ≥ 2x/week ( OR: 1.97; 95% CI: 1.52, 2.56) and ≤ 1x/week (OR: 1.57; 95% CI: 1.17, 2.10) compared to never being exposed to this marketing. Additionally, the odds of preferring McDonald’s decreased with increasing age.
By country, the odds of preferring McDonald’s when exposed to general fast food marketing ≥ 2x/week compared to never being exposed in a week were greatest in the US, followed by the UK, Canada and Australia (Table 3 ).
General exposure to all fast food marketing and preference for KFC
Compared to Canada, overall, respondents from all countries were more likely to prefer KFC more, with the odds being highest in Mexico, followed by Australia, the US, the UK, and Chile (Table 2 ). Females were also less likely to prefer KFC than males by a factor of 0.72 ( 95% CI: 0.62, 0.84). In terms of general exposure to fast food marketing, the likelihood of preferring KFC was highest when respondents reportedly viewed this type of marketing ≥ 2x/week ( OR: 1.61; 95% CI: 1.24, 2.09) and ≤ 1x/week ( OR: 1.54; 95% CI: 1.15, 2.07) compared to not at all.
By country, the odds of preferring KFC when exposed to general fast food marketing ≥ 2x/week compared to not being exposed to this marketing at all were highest in Chile, followed by Australia and the UK (Table 3 ). In terms of sociodemographic characteristics, female respondents in Australia and Canada had a significantly lower preference for KFC compared to males, and in Canada, individuals who identified as a minority ethnicity preferred KFC significantly more than those who identified as a majority ethnicity.
General exposure to all fast food marketing and preference for Subway
Overall, compared to Canada, the likelihood of preferring Subway was significantly lower in most countries, with the lowest odds in Chile, followed by Mexico, Australia and the UK (Table 2 ). When respondents were exposed to general fast food marketing, the odds of preferring Subway was highest when exposed ≥ 2x/week ( OR: 1.73; 95% CI: 1.34, 2.24) and ≤ 1x/week ( OR: 1.46; 95% CI: 1.09, 1.97) compared to not being exposed at all.
By country, in Mexico and the UK, the odds of preferring Subway were 2.8 times ( 95% CI: 1.33, 5.91) and 1.99 times greater ( 95% CI: 1.10, 3.61), respectively, when exposed to general fast food marketing ≥ 2x/week compared to never being exposed to this marketing in a week (Table 3 ). With respect to sociodemographic characteristics, in the UK, females were 1.57 times more likely ( 95% CI: 1.02, 2.41) to prefer Subway than males, and in Chile, those who reported perceiving their family to have enough money were 1.93 times more likely ( 95% CI: 1.20, 3.11) to prefer Subway than those who perceived their family to not have enough money.
Association between youth’s self-reported exposure to McDonald’s, Subway and KFC marketing and respective fast food brand preference
Exposure to only mcdonald’s marketing and preference for mcdonald’s.
In all countries, more respondents reported being exposed to McDonald’s marketing than not (Table 1 ). Mexico had the greatest number of exposed respondents (84% of respondents), and the UK had the smallest number of exposed respondents (66%).
Similar to the models above, overall, the odds of preferring McDonald’s were significantly higher in the UK and the US and significantly lower in Chile and Mexico compared to Canada (Table 4 ). When exposed to McDonald’s marketing, the odds of respondents preferring McDonald’s were 2.32 times higher ( 95% CI: 1.92, 2.79), compared to not being exposed. In terms of age, preference for McDonald’s decreased with increasing age.
By country, the odds of preferring McDonald’s were greater when exposed to McDonald’s marketing as opposed to not being exposed, with the highest odds being in Chile, followed by Australia, Mexico, the US, Canada and the UK. (Table 5 ).
Exposure to only KFC marketing and preference for KFC
In most countries, more respondents reported being exposed to KFC marketing than not (Table 1 ). Mexico had the greatest number of exposed respondents (83.9% of respondents), and the UK had the smallest number of exposed respondents (44.4%). Both the UK and Canada had more respondents who reported not being exposed to KFC marketing than being exposed (55.6% and 51.6%, respectively).
Similar to the previous models, compared to Canada, the odds of preferring KFC were significantly higher in all countries, with the highest odds of preference being in Australia, followed by Mexico, the UK, the US and Chile (Table 4 ). In terms of sex, females were less likely to prefer KFC than males. When reportedly viewing KFC marketing compared to not, the odds of preferring KFC were higher by a factor of 2.28 ( 95% CI: 1.95, 2.68).
By country, the odds of preferring KFC was higher in all countries when exposed to KFC marketing compared to not being exposed, with the greatest odds of preference in Canada, followed by Australia, the UK, Mexico, the US and Chile (Table 5 ). Females reportedly preferred KFC significantly less than males in Australia and Canada.
Exposure to only Subway marketing and preference for Subway
In the US, Canada and Mexico, more respondents reported being exposed to Subway marketing than not (70.1%, 68.8% and 61.9%, respectively) (Table 1 ). In the UK, Australia and Chile, more respondents reported not being exposed to Subway marketing than being exposed (65.8%, 52.5% and 50.8%, respectively).
Overall, the odds of preferring Subway were significantly lower in Chile, Mexico and Australia compared to Canada (Table 4 ). Additionally, respondents who reported being exposed to Subway marketing were significantly more likely to prefer Subway compared to those who were not exposed to this marketing ( OR: 2.75; 95% CI: 2.32, 3.27).
By country, the odds of preferring Subway in all countries was greater when exposed to Subway marketing compared to not being exposed, with the highest odds in the US, followed by the UK, Chile, Mexico, Australia and Canada (Table 5 ). In Chile, those who perceived their families to have enough money were more likely to prefer Subway than those who did not.
Association between youth’s self-reported general exposure to all fast food marketing and fast food intake
In most countries, the odds of fast food intake were highest when exposed to general fast food marketing ≥ 2x/week compared to reportedly never being exposed, with the highest odds being in Chile, followed by the UK, Canada, Mexico and the US (Table 6 ). In terms of sociodemographic variables, in four countries, the odds of reported intake were significantly lower for females than males. Additionally, in almost all countries, the odds of reported fast food intake were significantly higher for those who identified as a minority compared to those who identified as a majority.
Association between youth’s self-reported exposure to only McDonald’s, KFC or Subway marketing and fast food intake
Fast food intake and exposure to only mcdonald’s marketing.
In almost all countries, the odds of reported fast food intake were higher for those who were reportedly exposed to McDonald’s marketing compared to those who were not exposed, with the highest odds being in Chile, followed by Canada, the UK, the US and Mexico (Table 7 ). With respect to sociodemographic characteristics, in the UK, Australia, Canada and Chile, the odds of reportedly consuming fast food were significantly lower for females than males. With regard to ethnicity, in almost all countries, the odds of reportedly eating fast food was significantly higher amongst those who identified as a minority in their country as opposed to a majority.
Fast food intake and exposure to only KFC marketing
In almost all countries, the odds of reportedly consuming fast food were higher for those who were reportedly exposed to KFC marketing compared to those who were not, with the highest odds being in Canada, followed by the UK, the US, Chile and Mexico (Table 7 ). In terms of sex, in four countries, females reportedly ate fast food significantly less than males. In almost all countries, the odds of consuming fast food were higher amongst those who identified as a minority compared to those who identified as a majority.
Fast food intake and exposure to only Subway marketing
In all countries, the odds of reportedly eating fast food was significantly higher when exposed to Subway marketing as opposed to not being exposed, with the highest odds being in Chile, followed by the UK, Mexico, the US, Canada and Australia (Table 7 ). In terms of sex, in four countries, females reportedly ate fast food significantly less than males. The odds of consuming fast food were also significantly higher for those who identified as a minority compared to those who identified as a majority in almost all countries.
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 , 59 , 60 , 61 , 62 , 63 , 64 , 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 evidence on 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 14 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 to raise age thresholds beyond children, adopt more specific and uniform definitions for what is considered child marketing and implement more stringent HFSS thresholds.
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 [ 69 , 70 , 71 ]. 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 [ 72 , 73 ]. 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 [ 74 ]. 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 [ 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 ]. 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 [ 77 ].
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 the generalizability of our findings. Additionally, as the exposure measures did not specifically focus on marketing in particular types of 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 examine the power, ad content, frequency, and extent to which it targets the individual. Past research has shown that certain marketing techniques affect one’s recall of the advertisement, which could have altered their ability to remember marketing exposures [ 83 ]. While the self-reported fast food intake variable technically includes food intake from settings beyond fast food places (i.e., restaurants, food stands or vending machines), these other sources can arguably also be considered fast food-like, due to the ease of purchase and poor nutrient content of most foods sold from these sources. Additionally, it is possible that what respondents encompassed under ‘fast food advertising’ may have been interpreted differently by individuals, introducing additional bias. 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 necessarily accurately represent day-to-day choices [ 68 ]. Furthermore, existing evidence suggests that self-reported exposure measures are correlated with objective exposure measures [ 84 , 85 ]. 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, recruitment was completed using nonprobability-based sampling, meaning these findings may not be representative of national estimates. However, data were weighted by age group, sex, region, and ethnicity (except in Canada), which should mitigate this even if it did not completely remove the effect.
This study did not analyze these data by marketing policy jurisdiction, due to the complexities and differences in the policy inclusions/exclusions across the 6 countries and the cross-sectional nature of the data that cannot adjust for secular trends, as well as the sample not including children under the age of 10.
Overall, we found positive associations between exposure to fast food marketing and the brand preferences and reported intake of youth across all six countries. Regardless of the policy landscape surrounding restricting unhealthy food marketing to children, it is evident that exposure to fast food marketing is negatively influencing youth’s preference for and intake of these foods, as evidence has suggested that the odds of becoming overweight or developing obesity increases with fast food consumption [ 86 ]. The results demonstrate that current efforts to limit marketing to children and youth are not effective. As such, more comprehensive and stringent government regulation restricting fast food marketing to youth in all media may help reduce preferences and consumption of fast food. Including adolescents in these restrictions is also important, as they hold independent purchasing power, are easily influenced, spend a lot of time watching screens and have a high consumption of fast food products [ 24 , 25 , 71 , 87 ]. Future research should examine if and how these modelled associations differ by child and adolescent age groups. This research could provide preliminary evidence on the likely influence of marketing exposure on older youth on whom there is little research [ 64 ] and to investigate whether existing policies protecting children under 13 years old are effective in reducing exposure to fast food marketing and its consequences, such as brand preferences and intake.
Availability of data and materials
The data that support the findings from this study are available from the corresponding author under reasonable request.
High in fat, sugar and sodium
International Food Policy Study
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All methods were performed in accordance with the relevant guidelines and regulations for this journal.
Funding for this project was provided by an International Health Grant from the Public Health Agency of Canada (PHAC), with additional support from a Canadian Institutes of Health Research (CIHR) Project Grant (PJT-162167).
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Mariangela Bagnato, Marie-Hélène Roy-Gagnon & Monique Potvin Kent
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MB and MPK designed the study and MRG, MPK, CW, DH and LV oversaw the analysis. MB conducted the analysis and drafted the manuscript. All authors read and approved the final manuscript.
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Parents/guardians with a potentially eligible child were provided information about the study and asked to provide informed consent for their child to participate. Only one child per household was invited to participate. The child was subsequently screened directly to confirm eligibility based on age and sex. Children aged 10 to 17 years were eligible to participate, with quotas for age and sex groups in the UK and US. Eligible children were provided with information about the study and were asked to provide assent before beginning the survey.
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Bagnato, M., Roy-Gagnon, MH., Vanderlee, L. et al. The impact of fast food marketing on brand preferences and fast food intake of youth aged 10–17 across six countries. BMC Public Health 23 , 1436 (2023). https://doi.org/10.1186/s12889-023-16158-w
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DOI : https://doi.org/10.1186/s12889-023-16158-w
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Effects of Advertising on Food Consumption Preferences in Children
José antonio ponce-blandón.
1 Red Cross Nursing School, University of Seville, 41009 Seville, Spain; se.ajorzurc@ecnopaj (J.A.P.-B.); se.ajorzurc@nobapm (M.P.-C.); se.ajorzurc@oremorm (M.R.-M.); se.ajorzurc@ipijen (N.J.-P.)
Rocío romero-castillo, macarena romero-martín, nerea jiménez-picón, maría de las mercedes lomas-campos.
2 Faculty of Nursing, Physiotherapy and Podiatry, University of Seville, 41009 Seville, Spain; se.su@samolm
(1) Background: Childhood obesity is a public health problem. The purpose of this study was to know if exposure to commercial messages which advertise food products exerts any effect on the short-term consumption preferences of 4- to 6-year-old children. (2) Methods: A double-blind and randomized experimental design. Sample consisted of 421 boys and girls from twelve schools in a city in Spain. (3) Results: In three of the four product pairs shown, the products advertised in the intervention were preferred. In the results of applying the model for the first product pair presented, sugared cereals, the predictive variable which best explains the behavior of the preferences expressed is gender (Odds Ratio 0.285 (0.19–0.42); p < 0.05). For the second pair, chocolate cookies, the family’s nationality has a strong weight in the model. As regards the regression model calculated for the last pair (filled rolls), the predictive variable which showed having more influence was gender. Boys had a 1.39 times higher risk of selecting the advertised product than girls. (4) Conclusions: The persuasive effect of commercials has shown to be influential in a general, immediate, and significant way only in the case of products with wide brand awareness. This study reinforces the importance of advertising and emphasizes the need to initiate measures to control the content of TV commercials.
Childhood obesity is a public health problem. Overweight five-year-old children have a four to five times higher risk of being overweight in adolescence, and a significantly higher risk of obesity in adulthood [ 1 ]. According to the World Health Organization (WHO), the prevalence of obesity has risen at an alarming pace; it is estimated that, in 2016, more than 41 million children under the age of five worldwide were overweight or obese [ 2 ]. This population has more probabilities of suffering non-transmissible diseases at early ages, like diabetes and cardiovascular diseases. If the current trends are maintained, in 2022, there will be more obese children and adolescents than those with weight deficit and, in 2025, the world prevalence of obesity will reach 18% in men and will exceed 21% in women [ 3 ]. In Spain, the prevalence of childhood obesity is 34%, fourth place in the European Union countries [ 4 ]. The health bodies have requested regulatory measures which restrict the marketing of harmful foods for the health of children, including the advertising of unhealthy food products on television [ 2 , 5 , 6 ].
Zimmerman and Bell (2010) concluded that watching TV commercials was related to a higher Body Mass Index, whereas watching television without commercials was associated with a lower score in the Body Mass Index [ 7 ]. Simultaneously, fast food advertising has also been associated with the increase in the intake of unhealthy food products and in Body Mass Index [ 8 ]. Fast food, characterized by a large content of saturated fats and sugars, contributes to overweight and to incorrect nutrition in children [ 9 ]. Therefore, reducing the intake of fast food during preschool and school years is a simple way to improve children’s health.
The companies which produce fast food target children through attractive tactics, including bonds to renowned and admired characters and offering gifts when buying the products [ 10 ]. Additionally, it has been verified that the commercials in which a person appears consuming the product have more influence on the perception of consumers than those in which only the product is presented [ 11 ]. One of the effects of this type of commercial in children is imitation and the possibility of imagining and wishing to consume the product themselves [ 12 , 13 , 14 ]. Television is the main communication media used by companies to promote unhealthy food products [ 15 ], aimed at a vulnerable audience incapable of understanding the persuasive intention of advertising [ 16 ].
Studies on the effect on behavior have investigated the degree to which children are persuaded to buy or to ask for the advertised products or brands [ 17 ]. Different experimental studies have shown that children are more prone to select branded fast food products in detriment to the unbranded ones, and that they qualify branded food products as tastier than their unbranded equivalents [ 18 , 19 ]. Product advertising seeks to produce cognitive, affective, and/or behavioral responses in the audience, children in this case [ 20 ]. Hudson and Elliot (2013) found that the positioning of healthy and unhealthy food products had a slight influence on the immediate behavior [ 21 ]. However, van Reijmersdal et al. (2010) demonstrated a positive relation between exposure to brand positioning and the behavior of choosing it [ 22 ]. The preference for branded articles has been associated with the higher number of TV sets in the home, which suggests that exposure to TV commercials influences children’s preferences [ 1 , 23 ].
Despite the importance of the effect of TV food commercials on eating habits and on health, there is still a scarce number of studies which directly link food advertising to the intake of food products or to obesity, due to the difficulty in measuring the exposure to the commercials [ 8 ]. The studies conducted on this line have shown a weak support for the immediate effect on behavior, measured as willingness to buy or to consume immediately after exposure [ 20 ]. The fact that few studies have been conducted in Spain in this field reinforces the need to launch research studies which analyze the impact of advertising on the food consumption preferences of children in Spain. Concretely, the objective of this study is to know if exposure to commercial messages which advertise food products exerts any effect on the short-term consumption preferences of 4- to 6-year-old boys and girls. The main study hypothesis sets out that the children who watch child TV shows with food product commercials express more preferences for the advertised products than those who watch these same child TV shows without any advertising content. Secondarily, diverse hypotheses will be explored which set out possible relations among sex, age, nationality, and consumption preferences.
2. Materials and Methods
2.1. study design and sampling.
This study presents a double-blind and randomized experimental design. The study universe was a population of children between 4- and 6-years-old living in the city of Seville (Spain). This population is enrolled in 172 school centers, according to the statistics from the Education Council of the Andalusia Board [ 24 ].
To determine the sample size, the procedure established for hypothesis contrast studies, in which proportions are compared, was used. Specifically, considering that the minimum safety of the study must be 95% ( p < 0.05), that the test power (1-β) must also be of at least 95%, and using as value references the proportions of food products preferred by the children included in the study by Borzekowski and Robinson (2001) [ 25 ], that is, 54% of the children in the intervention group and 42% in the control group, the minimum size of each group had to be of at least 65 children. Taking into account that the choice was to recruit two control groups and two intervention groups, a minimum sample size of 260 children was needed, coming from a total study population of 13,945. To avoid selection bias which could suppose the loss of study subjects due to errors in data collection or to withdrawals, it was proposed to add a 10% safety margin to the sample, eventually leading to a minimum sample size of 286 subjects.
The sampling procedure employed was that of cluster sampling, stratified by center topology (public or private, including those of a concerted character in the latter), with Seville’s Child Education centers constituting the primary sampling units. Using as reference the figure of the mean number of pupils per group or class ratio, which is 23.6 pupils, and assuming that in each center, only one group was studied, it was estimated that a total of 12 centers were needed to complete the sample size, that is, 3 centers for each of the 4 study groups. A flow diagram of the sample recruitment is represented in Figure 1 , following the CONSORT model.
CONSORT flow diagram.
The cluster selection of these 12 centers was at random by using the systematic sample technique in each of the subgroups, employing a unit selection interval of 14, since the ratio between the total of centers and the number of centers (172/12) is 14.3. The 12 centers were obtained after selecting a random number obtained in the Microsoft ® Excel 2010 application and after applying the 14-unit interval. Subjects who did not have a television at home and children with dietary restrictions and allergic or intolerant to some foods were excluded of the study.
The study subjects were randomly allocated to four different groups. The four groups were exposed to watching an 8-min episode of the “Caillou” cartoon series, an animation character which is popular among children. The episode was called “ Caillou bombero ” (“Fireman Caillou”) and was selected with the aim that no reference was made to food consumption in its content. The control groups were groups 1 and 4, so that group 1 was exposed to the same cartoon episode but without commercials, whereas group 4 watched the same episode of “Caillou” with one commercial cut advertising different non-food articles (toys, objects, etc.). Children watched their assigned advertisement as a group on a single TV. Then, they went to a room individually where investigators exposed pairs of products.
The interventions groups were groups 2 and 3, so that group 2 watched this episode with one commercial cut which included 4 commercials of different food products aimed at a child audience. The products selected for advertising insertion were snacks and breakfast preparations of limited nutritional value and high fat and sugar contents. Group 3 watched the same cartoon episode but with two commercial cuts, so that in the second cut, the same four commercials were repeated.
The commercials used for the intervention were selected from those studied in Análisis de contenido de la publicidad de productos alimenticios dirigida a niños y a adultos en Andalucía (Content analysis of food product advertising aimed at children and adults) [ 26 , 27 ]. The content of 91 different food product commercials was studied, of which 39 were food commercials aimed at a child-youth audience; 41% advertised cereals, cookies, or cocoa, while 23.1%—dairy products. Two experts from the Andalusia Care Plan for Childhood Obesity were consulted to select the commercials meeting the following criteria [ 28 ]:
- ✓ Commercials of high fat and/or sugar content food products aimed at a child audience.
- ✓ Products aimed to be consumed at breakfast and included in the most frequently announced food groups: sugared cereals, cookies, cocoa, and dairy products.
- ✓ Including some commercial which employs special effects or fantastic situations, another which promotes giving some gift, collectible, or present, and a third one which uses the testimony of some famous character.
Thus, the following products were selected ( Figure 2 ):
Final voiceover with a slogan: “Mielpops, el desayuno más pop” (“Mielpops, the most pop breakfast”). Spot based on the use of shocking images and on fantastic situations by means of animation techniques.
Spot in which a famous Spanish soccer player explains the benefit of the product or his experiences related with it: “I like them with a lot of chocolate cream, like my Príncipe Double Choc”. This is a testimonial spot which uses the words of a celebrity as an advertising resource.
Final voiceover saying: “ Descubre el Club Batidos Puleva y podrás ganar Play Stations, juegos Sing Star y miles de regalos ” (“Discover the Puleva Shake Club and you can win Play Stations, Sing Star games, and thousands of presents”). Advertising version: “ Estos batidos son algo especial: Son batidos Puleva ” (“These shakes are something special. They are Puleva shakes”). Spot based on music and on visual experimentation.
Final voiceover saying: “ Ahora con los Bollycao únete a la banda de ‘Los Simpsons’ con los ‘bollytransfer’ ” (“Now with the Bollycaos, join the ‘The Simpsons’ gang with the ‘bollytransfers’”). Spot based on music and on visual experimentation. It also presents a gift inside the wrapping, a “bollytransfer”, which is a sticker with a character from “The Simpsons”.
Images of the products used for the choice method.
On the date scheduled, the researcher, together with a surveyor trained on the outcome measurement procedure but unaware of the allocated research group, approached the class tutor.
The children were invited to sit down in a room fitted out to watch cartoons. Afterwards, each child was individually directed to the research area. They were asked to select among some photographs shown in pairs, one of them with the article included in the commercial spot and the other showing a similar product. The products which were paired to the intervention participants were the following:
Product pair No. 1: Breakfast cereals:
Paired product: “Frostis” ( Kellogg’s ® ) breakfast cereals made with sugared wheat. Advertised product: “Miel Pops” ( Kellogg’s ® ) breakfast cereals made with popcorn and honey.
Product pair No. 2: Chocolate cream filled cookies:
Paired product: “Tosta Rica Chocoguay” ( Cuétara ® ) chocolate cream filled cookies. Advertised product: “Príncipe Double Choc” ( Galletas Lu ® ) chocolate cream filled cookies.
Product pair No. 3: Chocolate shakes:
Paired product: “ Pascual ® ” chocolate shakes. Advertised product: “ Puleva ® ” chocolate shakes.
Product pair No. 4: Filled roll:
Paired product: “Qé Tentación” ( Panrico ® ) chocolate filled roll. Advertised product: “Bollycao” ( Panrico ® ) chocolate filled roll.
The researcher, who was present at the time of the survey, recorded the child’s answer to each of the four advertised products in a collection sheet. In case the child did not answer or if contradictions were perceived in the answer, it was recorded as “not valid” and the participant was excluded from the study.
2.3. Data Collection and Analysis
The following were collected as descriptive general variables of the population’s sociodemographic characteristics: sex, type of center, and nationality; these were analyzed as independent variables. The dependent variables were established by studying the consumption preferences stated by the participants when shown the photographs of the four pairs of food products. The collected data were poured into a questionnaire elaborated with the Epi Info version 184.108.40.206 tool.
For the statistical analysis, the first steps were debugging the database and performing a descriptive analysis. For the frequencies of the qualitative variables, 95% confidence intervals for proportions were calculated, whereas the quantitative variables were numerically summarized by calculating the main measures of central tendency and dispersion. The Kolmogorov–Smirnov test was used to verify the normality of the “summation of the scores” variable based on the preferences from the pairs expressed by the participants. For the hypothesis contrast, Pearson’s χ 2 test was used, as well as Fisher’s Exact test as necessary, with a p value below 0.05 as the significance level. The Risk Ratio (RR) values were calculated, together with their confidence interval for 95%.
Finally, a multivariate analysis was performed to contrast all the predictive variables, which were contemplated in the different bivariate analyses, with assessment of the outcome: the preferences expressed by the participants for each pair of products presented. The multiple logistic regression technique was used to this end. For this, it was necessary to recode the preferences of each product pair to “dummy” variables, in which a value of “0” indicated choosing the non-advertised paired product and a value of “1” indicated choosing the advertised product. The independent variables included pertained to a control or intervention group, sex, and Spanish or foreign nationality. To build the multiple logistic regression model, Odds Ratios were calculated for each of the predictive variables introduced in the model, their confidence intervals for 95%, and the logistic regression coefficient. As well as the result of the statistical test and its significance level, the Newton–Raphson maximum likelihood method was used as a criterion to estimate the parameters. The Epi Info version 220.127.116.11 tool was used for data analysis.
2.4. Ethical Considerations
Authorization was obtained from the Research Ethics Committee of the University of Seville, as well as favorable reports from the Integral Care Plan for Childhood Obesity of the Andalusia Board and from the Seville Branch of the Education Council. Information meetings were conducted with parents and educators, and the father’s/mother’s or legal guardian’s informed consent was obtained for each of the study participants. Additionally, anonymity and the protection of personal data were guaranteed to the participants during data collection and analysis.
In the initial selection, 6 children were excluded for not having television at home and 28 children for having an allergy, intolerance, or dietary restriction. The sample eventually consisted of 421 boys and girls from twelve schools in the city of Seville ( Figure 1 ), with a mean age of 4.8 years (SD = 0.57; (4.74–4.85)). A total of 52% (47.1–56.9) were girls and 48% (43.1–52.9) were boys. Regarding their nationality, 93.1% (90.1–95.2) were Spanish, and the rest came from other countries. A total of 226 subjects participated in the control groups (53.7% (48.8–58.5)), whereas 195 participated in the intervention groups (46.3% (41.5–51.2)).
In relation to the results of the consumption preferences, in three of the four product pairs shown, the products advertised in the intervention were preferred, as can be seen in Table 1 . The bivariate contrast of the main hypothesis conducted with the preferences expressed for product pair no. 4 found significant differences between the control and intervention groups ( p < 0.05). No significant differences were observed for the rest of the products ( Table 1 ).
Distribution of consumption preferences for the sample as a whole and bivariate analyses by group.
As regards the hypothesis contrast between sex and consumption preferences, significant differences were observed for two of the product pairs presented. The girls said they mostly preferred the product advertised in pair no. 1, sugared cereals ( p < 0.05); the boys mostly preferred the product advertised in pair no. 2, chocolate cookies ( p < 0.05), with a relative risk of 1.98 and 1.54, respectively. As regards age (grouped into children younger and older than 5-years-old), no differences were appreciated in consumption preferences. In relation to nationality (grouped into Spanish and others), the preferences expressed for pair no. 2, chocolate cookies ( p < 0.05), and pair no. 4, filled rolls ( p < 0.05), were significant. Children coming from Spanish families preferred the advertised products more frequently than those of other nationalities ( Table 2 ).
Bivariate analyses of consumption preferences by sex and nationality.
A mean score was obtained after recoding the children’s preferences. It was necessary to recode the preferences of each product pair to “dummy” variables, in which a value of “0” indicated choosing the non-advertised paired product, and a value of “1” indicated choosing the advertised product. After coding, the researchers performed a summation of each child’s preferences, obtaining a unique value. In the first comparison, between the control and intervention groups, a mean score of 2.10 (SD = 1.02; (2.00–2.19)) was obtained in the children allocated to the control group, and of 2.17 (SD = 0.98; (2.07–2.26)) in those allocated to the intervention group. The variance values were 1.045 and 0.965, respectively. Once the normality of the outcome variable was verified, the Student’s t parametric test was applied, obtaining a result of 0.7008 which, for the 408 degrees of freedom (the valid answers in this test were 410), granted a significance level of p > 0.05. In this way, it was verified that there were no statistically significant differences in the scores obtained by the two groups.
In the comparison of the means and variances of the scores obtained by each of the four allocation groups, it was found that the mean score for group 1 (control without commercials) was 2.076 (SD = 0.97; (1.87–2.27), for group 2 (intervention with one commercial cut) 2.14 (SD = 0.94; (1.95–2.32)), for group 3 (intervention with two commercial cuts) 2.204 (SD = 1.02; (1.99–2.41)), and for group 4 (control with commercials of non-food products) 2.120 (SD = 1.06; (1.93–2.30)). Once the homogeneity of the variances was verified, the ANOVA parametric test was applied. This test showed that there were no statistically significant differences among the scores obtained in the four groups, since the value obtained was 0.262, which, for 3 degrees of freedom, corresponds to a significance level of p > 0.05.
In the results of applying the model for the first product pair presented, sugared cereals, the predictive variable which best explains the behavior of the preferences expressed is sex, with an Odds Ratio of 0.285 (0.19–0.42); p < 0.05. With equal behavior in the rest of the variables, the girls chose the advertised product 1/0.285 = 3.5 times more frequently ( Table 3 ).
Multiple logistic regression model for consumption preferences.
For the second pair, chocolate cookies, the family’s nationality has a strong weight in the model, an Odds Ratio of 0.383 (0.16–0.90) having been obtained, with a significance level of p < 0.05. Therefore, boys and girls of Spanish nationality present a 1/0.383 = 2.6 times higher risk of selecting the advertised product, “Príncipe Double Choc” chocolate cookies in this case. Sex once again appears as an important predictive variable in the model (Odds Ratio: 0.457 (0.30–0.68), p < 0.05). Consequently, the girls have a 1/0.457 = 2.18 times higher risk of selecting the advertised product than the boys, with equal behavior in the rest of the variables ( Table 3 ). The best multivariate logistic model establishes that: Logit ( p ) = 1.162 + (0.003 Group) − (0.959 Nationality) − (0.78 Sex).
In the regression model calculated for the third of the product pairs (cocoa shakes), none of the predictive variables showed any statistically significant influence. The variable which obtained a more influential result on the effect was age, with an Odds Ratio of 1.177 (0.8–1.7), but without a significant level of p > 0.05 ( Table 3 ). These results allow choosing the following as the best multivariate logistic model: Logit ( p ) = −0.117 − (0.05 Group) + (0.242 Nationality) − (0.385 Sex).
As regards the regression model calculated for the last pair (filled rolls), the predictive variable which showed having more influence on the preferences expressed was sex. The boys had a 1.39 times higher risk of selecting the advertised product than the girls, given equal values in the rest of the variables. Consequently, the Odds Ratio obtained for this variable was 1.299 (0.94–2.07), with a non-significant level ( p > 0.05) ( Table 3 ). The results shown establish the following as the best multivariate logistic model: Logit ( p ) = 0.589 + (0.299 Group) − (0.667 Nationality) + (0.336 Sex).
The aim of this study was to make contributions to the hypothesis which asserts that exposure to advertising messages for food products can have a direct influence on preschool boys’ and girls’ preferences and, indirectly, on their eating habits, from the search of possible risk factors that exert their influence on the high figures of childhood obesity and overweight that have been registered in the last years in our setting.
Various international multi-centric studies with heterogeneous populations have employed experimental methodologies similar to those in this study [ 29 , 30 , 31 , 32 ]. The most frequent experimental method is the exposure of the study subjects, in this case the children, to watching a cartoon TV show with commercial cuts in fitted-out rooms in the same school setting. It is a very usual methodology and of proved efficacy to evaluate the effect of advertising on the consumption preferences of children. In this study, the choice was to incorporate two control groups in order to minimize confusion biases. The decision to include a control group whose participants watch the same animation video with commercial cuts which include commercials for other non-food products has been made on account of previous clinical trials with similar hypotheses [ 33 , 34 ]. As regards the outcome assessment, based on the use of pairs of similar products shown to the study subjects, it has also been successfully employed in previous studies [ 18 , 31 ].
With respect to the results obtained, it is verified that, in the 4–6-year-old range, advertising does not seem to have a determinant effect on the immediate preference expressed, save for one of the products presented: the “Bollycao” roll filled with chocolate cream. For this product, advertising was able to exert its influence on the children’s preferences. Finding the immediate relation between advertising and preferences has been a persistent fact in the different stratifications and multivariate analyses performed. In the “Bollycao” commercial, a gift was offered when buying the product, which managed to exert some influence on the children’s choices. Authors like Kraak and Story (2015) have already found a relation between consumption preferences and offering gifts when buying products [ 10 ]. In that way, Kelly et al. (2008) particularly corroborated this hypothesis when the products advertised were not essential food products [ 35 ]. In this case, the brand’s memorability has also imposed some specific weight, since it manages to reach a phenomenon which Advertising calls “exclusivity of the brand” [ 36 ]. This means that a large part of Spanish society calls all industrial chocolate-filled rolls “Bollycao”.
The choice frequencies of the advertised product in the experimental group exceeded 50% for three of the products (“Bollycao”, “Miel pops” sugared cereals, and “Puleva” cocoa shakes), which denotes the general knowledge of these products by the participating children. In the United Kingdom, Boyland et al. (2011) verified that the children preferred food products with high fat or sugar contents if they were of a brand recognized from TV commercials [ 37 ]. Longacre et al. (2017) verified that exposure to TV commercials of cereals for children is associated with the family buying the advertised product [ 38 ]. According to Castetbon et al. (2012), households are 13 times more likely to buy those cereals aimed at children advertised on TV than unbranded cereals [ 39 ].
As regards the second product pair, chocolate cookies, the Spanish nationality presents a high weight on the regression model calculated. Boys and girls of Spanish nationality present a 2.6 times higher risk of selecting the advertised product, “Príncipe Double Choc cookies” in this case. This can be due to the presence of a renowned Spanish soccer player in the commercial. As already confirmed by Poor et al. (2013), commercials in which a person appears consuming the product have more influence on the perception of consumers than those in which only the product is presented [ 11 ]. This influence increases when the product is consumed by famous people, like sports celebrities [ 40 ].
The sex differences are consistent even when the sample is stratified by control and intervention groups. Many manufacturers from the food industry design products focused specifically on female and male child audiences. This has also been previously contrasted by Sixsmith and Furnham (2010), who found that, in the healthiest food commercials aimed at the child audience, more female characters and voices were used to attribute healthy properties to more feminine wishes [ 41 ], whereas those aimed at boys made use of sports celebrities [ 40 ]. This is a fact which has been contrasted in our study with the chocolate cookies product pair. Other authors concluded that children were more likely to choose foods with gender-consistent packaging and hypothesized that this effect may be explained by social norms. Children are motivated to fit into the gender expectations that they perceive [ 42 ].
One of the limitations of this study was assigning the preference expressed by the child, due to the age characteristics of the population. To this end, interviewers with experience in these age groups were selected. During the data collection period, some cases of uncertain answers were recorded, in concrete from 19 children, who were discarded from the sample to guarantee maximum debugging and quality of the results. Nevertheless, the consistency of the results could have been improved by assessing the outcome at two different times, with a pre-test and a post-test. However, this way to proceed is justified by the difficulty in making correct assessments in the young age range of the study population.
On the other hand, the influence of advertising demonstrated in this study is not as conclusive as in previous studies, as it has only been partially contrasted. This can be due to the fact that advertising is not the only factor related to eating habits and to consumption preferences but also family, educational, socioeconomic, and personal factors [ 41 , 43 ]. Because children are so heavily exposed to junk food advertising in the course of their normal lives, it can be challenging to detect the effects of brief experimental advertising interventions.
The persuasive effect of the commercials on the 4- to 6-year-old children under study has shown to be influential in a general, immediate, and significant way only in the case of products with wide brand awareness and a historical selling experience in the market.
This study reinforces the importance of advertising to a very vulnerable collective and emphasizes the need to initiate measures to control the deceitful and disturbing content of TV commercials. In this sense, further experimental research studies are needed to detect influences in order to better control and regulate the advertising of food products to the child audience, especially when the products’ nutritional values are not desirable.
Conceptualization, J.A.P.-B. and M.d.l.M.L.-C.; methodology, J.A.P.-B.; validation and formal analysis, M.P.C.; investigation, J.A.P.-B. and M.R.-M.; resources, N.J.-P.; data curation, M.P.-C.; writing—original draft preparation, R.R.-C.; writing—review and editing, R.R.-C. and J.A.P.-B.; visualization and supervision, M.d.l.M.L.-C. All authors have read and agreed to the published version of the manuscript.
This research received no external funding.
Conflicts of Interest
The authors declare no conflict of interest.
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