Body perception and frequency of exposure to advertising on social networks among adolescents

The marketing actions of influencers promoting unhealthy targeted products can aggravate the problem of childhood obesity and thus generate self-esteem problems. The influence of exposure to this type of sponsored content can also have an effect on the emotional well-being of adolescents. This is the context of this study, which seeks to analyze the relationship between exposure to food or body care advertising on social networks ( YouTube , Instagram , and TikTok ) of adolescents and their perception of their physical appearance. Online surveys were distributed between April and June 2022 to 1,055 adolescents aged 11-17 years and residing in Spain. The main results show that 16-and 17-year-olds have a heavier figure as an ideal reference


Introduction
The increased time spent by adolescents in the digital environment, may involve a risk that has an impact on health, both directly and indirectly (WHO, 2022). Thus, on the one hand, the increased consumption of content through social networks such as TikTok, YouTube, and Instagram, means less time available for sports practice. On the other hand, the greater number of hours of use also means being impacted to a greater extent by advertising (González-Díaz, 2014;WHO, 2022). Food products with high levels of saturated fats, salt, and/or sugar are some of the most recurrent advertising categories (Boyland et al., 2016;Coates et al., 2019;Bugueño, 2020), which can lead to increased consumption of unhealthy foods by children (Sadeghirad et al., 2016;Murphy et al., 2020; Reyes-Pedraza; García-González; Téllez-Castilla, 2020).
The high levels of prevalence of both childhood obesity and being overweight have forced governments around the world to develop surveillance tools to assess and design corrective measures (WHO, 2021;Gobierno de España, 2022). Although this is an international problem, data indicate higher levels of obesity and being overweight in Mediterranean and Eastern European countries (WHO, 2021).
In Spain specifically, the prevalence of childhood obesity stands at 17.3%, while being overweight is at 23.3%; that is, 4 out of 10 children suffer from one of these disorders (Aesan, 2019). The causes that have led to the increase in the prevalence of childhood obesity are diverse and multifactorial (González-Díaz, 2014; De-Jongh-González; Escalante-Izeta; Ojeda-García, 2023) and cover very different areas, including health, education, or the economy (WHO, 2022).
Furthermore, there is also the influence of media exposure on the emotional well-being of children. A private research leak from the Facebook team has highlighted that simply consuming certain content on social networks influences the mood of younger people: more than 40% of Instagram users acknowledged that the feeling of being unattractive started while using the app (Milmo;Skopeliti, 2021). Experts insist on the need to control and regulate algorithms that choose and adapt the photos and videos a user sees according to their usage, potentially creating a spiral of harmful content; others reinforce the idea of educating young people on how to navigate a world dominated by social networks, equipping them with tools to make healthy choices for themselves (Milmo;Skopeliti, 2021).
Following Unicef Spain's recommendations to address the concerns of children and adolescents and to promote the practice of healthy habits (Unicef, 2021), this study seeks to analyze the influence that exposure to food and body care advertising on social networks has on their perceptions of their physical appearance.

Advertising in the digital environment
The decline in the effectiveness of online advertising in its most classic formats (banners, pop-ups, or skyscrapers) and the growing trend toward the use of tools to block it (ad blockers) prompted the emergence of so-called native advertising, which developed mainly on social networks and is characterized by respecting the editorial style of the platform on which it is added (Wojdynski; Golan, 2016; Gómez-Nieto, 2018; Eyada; Milla, 2020). Therefore, the delimitation of advertising spaces and formats is not as clear as in advertising disseminated through traditional mass media, which requires that this content be accompanied by a legend mentioning their advertising nature to facilitate their identification as commercial messages (Wojdynski;Golan, 2016).
It is in this context that influencers appear, who, according to the definition developed by Autocontrol, are "people with a high level of influence on the public due to their high number of followers on social networks and/or in digital communications media and who interact through tweets, videos, and posts as well as through messages on blogs or other websites" (Autocontrol, 2021). In addition, their main arena of action is social networks.

Funding
This study is conducted within the Digital_Fit research project: "Body and diet as sales arguments on social networks: Impact of brand content published by influencers on the beliefs of minors on physical appearance and healthy eating habits," funded by the Mapfre Foundation.
This implies that the audience may have greater difficulty in perceiving that it is content for commercial purposes Marketing by influencers also benefits from the parasocial relationships that are established between the sender and the receiver, which result in influencers' being perceived not as content creators with an economic objective but rather as "close and intimate friends" (Lim et al., 2017;Meyers et al., 2017;Conde;Casais, 2023). The stronger such parasocial interaction with influencers, the more likely it is that the audience will perceive authenticity in the messages they convey and interest in the recommendations they make (Djafarova; Rushworth, 2017; Audrezet; De-Kerviler; Moulard, 2020; Silva et al., 2021).
In a context in which physical appearance is increasingly important and in which influencers consolidate ideal physical traits that then turn them into archetypes of beauty and influence the care of physical health (Rosara; Luthfia, 2020), more caution should be taken with these types of self-interested recommendations. Scientific evidence has shown, particularly in the case of adolescents, that they are influenced in terms of not only their eating patterns, but also their body image perception (Coates et al., 2019; Tiggemann; Anderberg, 2020; De-Jans et al., 2021; Lowe-Calverley; Grieve, 2021). This means that, by promoting unhealthy food products, influencers may be contributing to the aggravation of the childhood obesity problem, as well as related emotional and self-esteem problems (De-Jans et al., 2021).
The aim of this research is to analyze the relationship between exposure to advertising on social networks of adolescents (YouTube, Instagram, and TikTok) and the perception they have regarding their body, as well as the impact on the level of satisfaction with their physical appearance and its social relevance. To this end, the following research questions are posed: RQ 1. Is there an association between the level of exposure that adolescents have with food or body care advertising on social networks and: -the perception they have of their bodies and -their level of satisfaction with their physical appearance and its social relevance? RQ 2. Do the age and gender of adolescents introduce significant differences around: -the perception they have of their bodies and -their level of satisfaction with their physical appearance and its social relevance?

Methodology
To collect information, a questionnaire was developed on the basis of previous work (Lou; Yuan, 2019; Smit et al., 2020; Cambronero-Saiz; Segarra-Saavedra; Cristófol-Rodríguez, 2021; De-Jans et al., 2021), and was given to adolescents between 11 and 17 years of age residing in Spain. A total of 1055 individuals participated, with a 95% confidence level and a ±3% margin of error.
The sampling procedure was multistage, stratified with proportional allocation. It used as first stratum four ad hoc aggregated geographical areas (following the classification of NUT areas used by the EU), and a second level of stratification according to the socioeconomic level of the families (low, medium, and high). The final selection of the individuals to be surveyed was made according to cross quotas of gender and age.
The distribution of the sample according to the adolescents' age is 28.3% aged 11-12 years; 44% aged 13-15 years, and 27.7% aged 16-17 years; while by gender, 53.6% are male, 46.3% female, and 0.1% other. In terms of socioeconomic level, 30.2% were low, 50.4% medium, and 19.3% high. The questionnaire was distributed online through the survio. com platform, which, with the support of a social studies company, enabled the participation of adolescents from all the autonomous communities of Spain. Field work was conducted between April and June 2022.
To safeguard the integrity of the study participants and the researchers, authorization for the collection of information was requested from the minor's guardian by means of a signed informed consent form, previously validated by the Ethics Committee of the university to which this research is attached (Universidad Internacional de la Rioja), which also reviewed and approved the methodological design of the project.
The publications of the influencers in social networks affect the mood of the youngest, both in the perception of their body image and in the choice of their dietary guidelines

Measurement
This study included the measurement of three groups of variables: perception of the adolescent's current and ideal figures; level of satisfaction with their physical appearance and its social relevance; and frequency of exposure to food or body care advertising on social networks (YouTube, Instagram, and TikTok).
1) For the variables relating to the adolescent's perception of their ideal (FIG_ID) and current (FIG_AC) figures, the Thompson and Gray (1995) Silhouette Test was used as a reference to establish the body image that they consider ideal and the body image they have of themselves. This scale is composed of nine drawings that identify physical shape, from value 1 as very thin to value 9 as very fat, for both men and women. The calculation of the means indicates that the adolescents surveyed tend to perceive their current figure as fatter than their ideal figure (FIG_ID M = 5.76; FIG_AC M = 5.82).
2) Level of satisfaction with their physical appearance and its social relevance: in this case, the aim was to assess the degree of acceptance adolescents have of their physical appearance and the influence they give to body and appearance in social relations. Thus, the following four questions were formulated, previously tested in similar studies (Fanjul-Peyró; López-Font; González-Oñate, 2019): -"Do you feel satisfied with your body and physical appearance in general?" (ASP_FIS1); -"Do you think that others' perception of you would improve if your physical appearance changed?" (ASP_FIS2); -"Do you think that having a good physique helps you to be more successful (more friends, be liked more, be more accepted, etc.)?" (ASP_FIS3); -"How important do you think your friends think your physical appearance is?" (ASP_FIS4), We used a five-point Likert scale in which 1 = not at all and 5 = very much. The averages were as follows: ASP_FIS1 M = 3.68; ASP_FIS2 M = 2.76; ASP_FIS3 M = 3.32; and ASP_FIS4 M = 3.38, indicating that in general their degree of satisfaction with their body is higher than the impact that physical appearance can have in society.
3) Frequency of exposure to food or body care advertising on social networks (EXP): in this case, the frequency with which adolescents receive advertising about food or body care on YouTube (EXP_YT), Instagram (EXP_IG), and TikTok (EXP_TK) was assessed. The following question was asked: "How often do you receive food or body care advertising on the following platforms?" The frequency of exposure to advertising was measured using a six-point Likert scale, where 1 = never (because I do not use this platform); 2 = never; 3 = infrequent; 4 = somewhat frequent; 5 = frequent; and 6 = very frequent. The calculation of averages reflects that adolescents perceive more advertising on this topic on YouTube, followed by TikTok, and in third place, Instagram (EXP_YT M = 4.04; EXP_TK M = 3.51; EXP_IG M = 3.27).
Statistical analysis was performed using the SPSS software package version 25.0. To answer question 1, bivariate analyses were performed using Pearson's tests to analyze the relationship between exposure to advertising, perception of their bodies, and level of satisfaction with their bodies. regarding RQ2, the Anova test was applied to determine whether there is a relationship of dependence between the variables analyzed and the filter variables (gender and age).

Relationship between exposure to social media advertising and body perception and satisfaction
3.1.1. Body perception and exposure to advertising on social networks Bivariate analyses using the overall sample revealed no significant correlations between adolescents' perception of ideal/actual figure and their exposure to food and body care advertising on YouTube, Instagram, and TikTok (p > 0.05), as reported in Table 1.
However, what was observed is that there is a positive and relevant association between the respondents' ideal and real perceptions of their body (p < 0.01). Although exposure to advertising on social networks does not affect the perception of the ideal figure, the variables defined to measure the social relevance given to physical appearance do; thus, the ideal perception correlates negatively with the importance of physique in the perception of others (p < 0.01), with the perception that success goes hand in hand with a good physique (p < 0.01), and with the importance given to physical appearance by their friends (p < 0.01). However, the current perception variable correlates negatively with the level of satisfaction with their body (p < 0.05).  Thompson and Gray Silhouette Test (1995) Exposure to advertising on social networks influences the level of satisfaction that minors express with their own bodies, more pronouncedly among those between 16 and 17 years of age

Level of satisfaction with physical appearance, social relevance, and exposure to advertising on social networks
In this case, bivariate analyses show significant correlations between the level of satisfaction expressed by adolescents regarding their bodies and exposure to advertising on social networks (Table 1). A negative association was observed between the satisfaction variable and exposure to YouTube (p < 0.01), Instagram (p < 0.01), and TikTok (p < 0.01) variables, with the strongest association being with that which is seen on TikTok.
Likewise, all the variables designed to measure the social relevance that adolescents give to their bodies -the importance of physique in the perception of others (ASP_FIS2); the level of social success according to physique (ASP_FIS3); the relevance that friends give to a good physique (ASP_FIS4)-correlate positively (p < 0.01) with the variables of advertising exposure on YouTube, Instagram, and TikTok. Across all variables, the correlation is strongest on Instagram and TikTok.
Furthermore, it is also interesting to note that the level of satisfaction shows a negative association (p < 0.01) with the social relevance of the body variables (ASP_FIS2; ASP_FIS3; ASP_FIS4).

Differences by gender and age
If the gender-differentiated means are compared, it can be seen that girls tend to choose a fatter ideal figure as a reference than boys, something that is also registered in the choice of figure that represents their current state (FIG_AC), as presented in Table 2. Likewise, boys reported a higher level of satisfaction with their bodies than girls and also perceive to a greater extent than girls that physique influences the perception that others have of us and that the level of social success is commensurate with the physique we have. Girls, however, are more likely than boys to believe that body care is important to their friends. However, the Anova test did not show significant differences according to gender, as presented in Table 3. When the sample is differentiated by age, it can be observed that the oldest participants (16-17 years old) have a fatter figure as an ideal reference, however, this is also the group that presents a thinner evaluation of their current figure.
In addition, their level of satisfaction is the lowest compared with the rest of the age groups. Along the same lines, the oldest group is the one that gives more importance to the social role of a good physical appearance, while the youngest group (11-12 years old) is the one that gives less value to these variables (Table 4). As a function of age, certain significant differences are observed in the variables defined to assess social relevance of the body (ASP_FIS2; ASP_FIS3; ASP_FIS4), as presented in Table 5.

Discussion
Although the body positive movement, which promotes the acceptance and normalization of body diversity (Cohen; Newton-John; Slater, 2021), is currently gaining more and more strength on social networks, there are still many representations on social networks that continue to be based on traditional models in which the archetype of the ideal body has attributes such as youth and thinness.
Furthermore, continuing to utilize these types of unattainable ideals has led to a high number of people reporting that they do not feel attractive after having started to use social networks (Markey;Daniels, 2022;Fioravanti et al., 2022).
In this sense, the results of our work have confirmed that there are significant correlations between the level of exposure of adolescents to food or body care advertising on social networks and the level of satisfaction with their physical appearance (RQ 1). Specifically, the data show that exposure to social networks increases the dissatisfaction that adolescents have with their own bodies, which, as previous studies have shown, can lead to the development of mental health problems such as depressive disorders (Murray et al., 2023), self-esteem problems due to feeling that they do not fit in with the canons of beauty established by society (De-Jans et al., 2021) and agreed upon by social networks, and eating disorders (Cordero et al., 2022;Pink et al., 2022;Sanzari et al., 2023).
When comparing ideal and real figure, girls consider that they are above the ideal weight, while boys consider that they are below In terms of level of exposure and social relevance, we also observed that, the greater the exposure to advertising on social networks such as YouTube, Instagram, and TikTok, the more important they believe physical appearance is to others, both to friends and to people with whom they have a more distant or no relationship.
In addition, they also consider that people who are closer to the established ideal of beauty will have a higher level of social success. Although this relationship was found in both genders, boys reported having this perception more frequently than girls.
In contrast to previous studies, no significant differences were found between the beauty ideals of boys and girls when analyzing the results by gender (RQ 2). However, in the case of girls, the ideal figure corresponds to one that is comparatively thinner than in the case of the figure chosen by boys. Furthermore, when it comes to comparing ideal and actual figures, girls consider themselves to be above the ideal weight, while boys consider themselves to be below.
This once again highlights the need to incorporate the gender perspective both in the analysis of health problems and in the proposal of interventions (Álvarez-Díaz, 2020), since gender is a key structural determinant (WHO, 2018) that seeks the identification and consideration of differences in the socialization of women and men. In addition, it is also considered a pillar on which the development of values, attitudes, and behaviors is based (Borrell; Artazcoz, 2008).
Significant differences in the level of satisfaction with physical appearance and its social relevance (RQ 2) are seen when it comes to age: it was found that the level of satisfaction is lower in the group between 16 and 17 years of age, and that in turn, this group is the one that attaches the greatest importance to the social role of having a good physical appearance. Therefore, although they have greater cognitive development to critically process advertising content, they are the most vulnerable audience to this type of advertising exposure on social networks.

Conclusions
The results of our study show that exposure to advertising by influencers on social networks such as YouTube, Instagram, and TikTok does not influence adolescents' perception of their own bodies, but it is directly related to lower body satisfaction.
This assessment is based not so much on individual reasons related to health or personal well-being, but mainly on social reasons, which increase in importance with age as the participants consider that physical appearance can affect the consideration that others have of them and be a determining factor for social success.
Among the main limitations of the study are that the methodological tool used does not allow us to delve into the impact that advertising by influencers on social networks has on the choice of products, nor does it evaluate the advertised products' nutritional quality or the usefulness of care, so it would be interesting to complement the results of this work with other qualitative methodologies or with a content analysis of the products advertised.
In addition, given these findings, we believe that it would be interesting for future lines of research to conduct a study that allows us to delve into the impact that the physical appearance of the influencer may have on adolescents' intention to purchase food and body care products, as well as to delve into the beliefs that condition their body satisfaction.
Finally, one of the main contributions of the study is the establishment of a tested and updated quantitative methodology that allows for its replication in the future in other countries and regions, with the aim of evaluating the effectiveness of possible actions to improve critical competencies in the face of idealized content and that which has a persuasive intentionality, as recommended in the European regional report on obesity (WHO, 2022).

References
Aesan ( There is no association between exposure to advertising and perception of one's own body