Eating disorders (EDs) are impairing and chronic psychological disorders characterized by disturbances in body image and eating behaviors [1, 2]. Central aspects of ED psychopathology, including body and weight concerns, and body dissatisfaction can be influenced by sociocultural factors, with mass media being the most impactful one [3]. Ideal body shapes conveyed by traditional mass media, such as magazines and television, comprise unattainably thin and toned bodies, exalting slenderness, and weight loss [4]. The relationship between traditional media exposure and body image disturbances has been supported by a large number of correlational and experimental studies both among women [for a meta-analysis see 5] and men [for a meta-analysis see 6]. According to the sociocultural theory of body dissatisfaction [7] there are two mechanisms involved in this relationship: (i) internalization of appearance ideals (e.g., thin, muscular, and fit ideals); (ii) appearance-based social comparison. Specifically, frequent media exposure leads individuals to internalize the “ideal thin” as beautiful and desirable, and compare themselves to these idealized images, engendering a dissatisfaction towards their body and appearance [8].
Although traditional media are still largely used, other types of “new” media are being increasingly diffused, most evidently the Social Networking Sites (SNSs). SNSs are online platforms where users can create and share content with other users [9]. These sites differ from traditional media in two main aspects: (i) they are interactive; (ii) the content is mostly generated by peers [10]. Users are simultaneously information sources and receivers, they can actively decide their participation by creating their own profiles and posts, browsing the information posted by other users and interacting with them by means of “likes” and comments. The negative influence of using and being exposed to SNSs on body image has been recently evidenced by an emerging body of research. Specifically, a wide number of studies have found that SNS use is associated with body dissatisfaction and disorderly eating among young women and men [for a systematic review, see 11, 12; for a meta-analysis, see 13]. Internalization of beauty ideals, appearance-based comparison and self-objectification were found to explain the detrimental effect of SNS use on body image [11], providing support for both the social comparison [7] and objectification theory (i.e., internalization of an observer's perspective as the primary view of the physical self) [14] in the field of SNSs. Indeed, like traditional media, SNSs are often appearance-focused since users post photos in which they look good and attractive, enhanced by the application of filters or digital editing tools, and composed [15]. As a result, many of the presented images on SNSs are idealized and unrealistically attractive, which may have a role in inducing body dissatisfaction. Moreover, although the majority of the studies have investigated the effect of the exposure to idealized images on SNSs on the general/evaluative component of body image (i.e., body satisfaction/dissatisfaction), those studies that have investigated the impact of SNSs on cognitive (appearance self-esteem and psychological body investment) and behavioral (disordered behaviors related to body image) dimensions of body image found higher effect sizes [13].
Noteworthy, studies that assessed the relationship between appearance-focused social media use and body image obtained a stronger effect size than studies that investigated general social media use [11, 13], suggesting that future research would benefit from investigating more image-based SNSs, such as Instagram. In addition to its raising popularity, compared to other popular SNS such as Facebook or Twitter, Instagram uniquely focuses on image-based content such as photo and video updates, and provides an in-built tool that offers several possible filters to enhance the appearance of a photo. Thus, Instagram users are not only more likely to promote an idealized self-image but also to be exposed to other users' idealized images (rather than real ones), and this could increase upward appearance-based comparisons and their negative effects on body image. An increase in body dissatisfaction following exposure to idealized Instagram images of thin and attractive women relative to control images was found [16–18]. Moreover, the exposure to fitspiration images (i.e., people usually exercising, or dressed in exercise outfits) was also associated with the development of body image dissatisfaction [19–22]. Indeed, content analyses showed that fitspiration images, albeit focused on fitness and health, foster weight loss and place particular value on physical appearance, depicting only thin and toned models [23]. A recent systematic review examining the state-of-the art on the relationship between Instagram use and different mental health indicators, obtained most evidence for the relationship between intensity of Instagram use and social comparison, body dissatisfaction, dietary behaviors, and disordered eating outcomes [24]. Finally, Griffiths et al. [25] found that exposure to both thinspiration and fitspiration contents on image-centric social media was associated with more frequent physical appearance comparisons, and through these, greater symptom severity among a clinical sample of individuals with EDs. These results, as a whole, suggest that the likelihood of developing EDs symptoms might be enhanced among those people reporting a lack of self-regulation in one’s own use of Instagram, often named Problematic Instagram Use (PIU). Based on the six components model of Griffiths (2005), PIU has been defined as a maladaptive engagement with SNSs leading to impairment in personal, social, and vocational/academic functioning. Very recent studies have shown that PIU negatively impact body esteem through the mediating role of physical appearance perfectionism, that is, concerns about imperfection [26], in keeping with previous findings supporting a positive association between Problematic Social Networking Sites Use and lower body and self-esteem and higher ED symptoms/concerns [27]. Moreover, PIU was found to be associated with elevated body image dissatisfaction which in turn was related to increased psychopathological symptoms [28].
To date we are unaware of any study that has specifically examined the association between PIU and eating disorders psychopathology. Research on this topic is relevant because there are multiple reasons to believe that a compulsive and unregulated use of Instagram might be related with onset and persistence of eating disorders (EDs) psychopathology. In particular, body image concerns, a central aspect of ED psychopathology, as aforementioned, can be induced by exposure to idealized images found on SNSs, especially on those focused-on appearance-based content, such as Instagram. Despite the lack of empirical evidence concerning the relationship between PIU and body image concerns, the frequency of Instagram use has been reported to predict higher body dissatisfaction [29, 30]. Therefore, it is reasonable to assume that body image concerns might explain the relationship between PIU and eating disorders psychopathological symptoms. A mediating role of body dissatisfaction in the relationship between PIU and different psychopathological outcomes including loneliness, depression, anxiety, and social anxiety was evidenced by a previous recent study [28]. Additionally, previous systematic reviews [11, 12], indicated appearance-based social comparison as one of the main explaining mechanisms of the negative effect of SNSs use on body image. According to social comparison theory, individuals tend to compare their opinions and abilities with others’ opinions and abilities [31]. Young women exposed to thin ideal body images appear to automatically engage in social comparison when viewing SNSs idealized images, thus inducing body dissatisfaction. Therefore, it is plausible to suppose that the appearance-based comparison might explain the relationship between PIU and body image concerns. In addition, it was found that the relationship between appearance-focused social media use and body image disturbance was stronger when considering the cognitive dimensions of body image such as the psychological investment in physical appearance [13]. It is possible that the continuous exposure to idealized images found on Instagram may lead females to attach more importance to the way they look like and consequently to feel more concerned about their body. For this reason, psychological investment in physical appearance might be a further underlying mechanism for the relationship between PIU and body image concerns.
Despite the extant literature, it has not been empirically shown how PIU affects eating disorders psychopathology both in general and in clinical population and less is known about the mediating role of appearance-based comparison tendency, psychological body investment and body image concerns on this effect.
The current study aims to fill this gap by investigating PIU amongst individuals with eating disorders and comparing PIU levels in young women with and without EDs. Based on the above-mentioned evidence we expected women with ED symptoms to show more PIU levels, as well as a higher tendency to make appearance comparisons on Instagram, with respect to women without ED symptoms. Moreover, as no previous study has investigated the potential psychological processes underlying the link between PIU and EDs, the current study wanted to evaluate a model explaining how PIU relates to ED psychopathology on young women, considering the mediating role of specific dimensions of body image (i.e., psychological body investment and body uneasiness) and appearance comparison tendency. More specifically, it was hypothesized that PIU would lead a person to make more frequent physical appearance comparisons and increase his/her psychological investment in physical appearance, thereby causing body uneasiness. Body uneasiness would, in turn, predict ED symptoms and related interpersonal difficulties (Fig. 1).