Prior to the emergence of ICT the self-help approach – following a diet or programme without professional help or support - offered the lowest cost weight management strategy [
21]. It has been speculated that web-based weight management programmes may provide another cost-effective alternative to conventional therapies (e.g. in-person weight management treatments). One study examined the differences in cost per person between two group weight loss programmes, one delivered in-person and the other via group internet ‘chat’ sessions, and while both groups demonstrated clinically meaningful weight loss, the in-person group showed significantly better weight loss than the internet group by the end of the six month intervention period [
58]. On the other hand, economic analysis revealed that not only did the internet-delivered weight management programme cost less per person it also cost less per kilogram lost [
58].
As weight regain after weight loss is very common [
4], the cost of continuing care needs to be taken into account after weight loss. A weight loss maintenance trial was conducted following successful weight loss, compared the cost-effectiveness of a ‘personal contact’ programme to an internet-delivered programme, and found the internet-delivered programme to cost less, however only the in-person treatment produced statistically significant weight loss [
59]. Social media may be an even less expensive avenue, particularly if an existing platform (e.g. Facebook) is used for programme delivery. The interactivity of social media together with user-generated content may provide a friendly environment and enhance the outcomes of such interventions.
Online interactivity
Including an interactive component to an intervention may be especially helpful for intractable public health conditions such as obesity, and may provide cost-effective and accessible weight management interventions [
60]. A systematic review and meta-analysis investigated behavioural physical activity (PA) and dietary weight management interventions that utilised social networking features and noted that message board services provided as a part of internet-delivered interventions were the most commonly used [
61]. The analysis failed to find statistically significant differences in primary outcomes (such as weight, BMI and PA levels), and in the few studies that reported improvements, the changes were not maintained [
61]. However, these findings may be the result of inconsistencies between the intervention protocols, as there was a fair degree of heterogeneity between the trials reviewed. Furthermore, the studies where reductions to BMI or weight were primary outcomes, this review reported a variety of weight management programmes, of varying durations, across different age ranges, and was not limited to participants with a high BMI only [
61].
A systematic review and meta-analysis of weight management trials that incorporated elements of online social networking found a small, but statistically significant reduction in BMI in the intervention groups at six months, which tapered off by 12 months, which is similar to findings in conventional weight loss interventions [
60], where weight regain after initial weight loss is a common phenomenon [
4]. Furthermore, there were no significant differences in any of the other primary measures (such as blood lipid profiles, body fat composition, weight, waist circumference and blood pressure), and participant retention was found to be problematic [
60]. Again, the degree of heterogeneity between study protocols may have influenced these results. Of note, social support was not reported in neither this study nor the study conducted by Williams and colleagues (noted above), so it is unclear if participants were encouraged to make use of social networking features in this way.
While systematic reviews provide a broad overview of the specific interventions types under investigation, the finer details of the studies reviewed often escape analysis. An assessment of individual studies that have used social media to assist with weight management shows that many interventions have used a combination of ICT as a part of the study protocol, including Twitter, Facebook, text messaging, podcasts, and mobile phone apps. In addition, these studies have sometimes included contact with a trained professional via such media, usually text messages. A weight loss trial using Twitter for social support with programme content delivered via podcasts and mobile phone app, found that degree of usage was positively associated with weight loss although it was not clear whether Twitter use assisted weight loss or participants losing weight ‘shared’ more, as not all participants engaged with Twitter, and usage declined over time [
62]. Interestingly, participants’ Twitter posts were examined for elements of social support with the results showing that informational support was predominant, emotional support increased over time, however there was no evidence of material support [
62]. Similarly, a study of the Weight Watchers Facebook page to examined members’ perceptions of social support reported that the majority of members derived both informational and emotional support through the site [
63], however weight loss data was not collected in this study.
On the other hand, some social media weight management trials reported a statistically significant intervention effect i.e. weight loss, but did not report on the degree or type of social support received by participants. One such study used Facebook to provide weight management programme content (including podcasts), together with text messaging to programme strategy reminders, recorded weight loss in the intervention group [
64]. Participants were also required to have a support ‘buddy’ from outside of the study group, and received personalised feedback, but even so social support was not reported [
64]. Another similar trial used text messaging for two-way communication between a trained health coach and participants - to send weight management strategies and receive participants’ progress reports – with Facebook for social support, reported weight loss in the intervention group [
65]. Despite having a Facebook group and personalised feedback from the health coach social support was not measured in this study [
65]. Contrary to the majority of weight management interventions, participant retention was high in both this and the previously-mentioned study, however both trials were of relatively short duration [
64,
65].
Judging by the studies reviewed, weight management interventions that utilise social media tend to measure either changes to weight and other risk factors or level of social support, but rarely the two together. By including a combination of ICT within the same intervention the exact cause/s of the resultant outcomes can be difficult to determine. In order to more fully understand how to make best use of social media as a vehicle for weight management interventions, emerging research has begun to examine changes to weight and other risk factors alongside outcome measures associated with social support, using one social media platform only e.g. Facebook [
66].
Due to the complex nature of weight loss and regain [
4], social support provided via social media may be a useful tool to include in multifactorial weight management interventions. Research cited in this review demonstrates that social media may be an acceptable supplement or even substitute for offline social support for individuals undergoing health behaviour changes (including weight management), and may be important especially if offline social support is inadequate. Similarly, information sharing can be gained by belonging to social media support groups, and this may provide a useful supplementary service for participants between visits to their health care practitioners, especially where distance can make accessing services difficult. Participant retention seems to be problematic, but this issue is not limited to weight management [
21] or social media [
67] interventions. Until the root cause/s of participant attrition are identified, high drop-out rates will continue to plague weight management interventions, regardless of how they are delivered.
Potential pitfalls
The ability of users to generate and/or share content may create the potential to disseminate incorrect information [
45,
60], which could apply to any intervention conducted without professional involvement [
21]. Social media can also be a distraction, leading to the overconsumption of food [
68]. In addition, food posts have been shown to make an individual’s desire eat when not hungry [
68]. Considering the ubiquity and accessibility of ICT, protecting the privacy, data and confidentiality of intervention group members is another concern that has been raised [
49]. Some researchers have speculated that engaging with unknown individuals may be a relevant concern [
44], while other researchers have suggested that the generation/use of health-specific sites may allay some of these concerns, as participants may feel they can trust those that they can relate to [
54]. Others have suggested that participants’ online privacy should be treated with same confidentiality as when patients receive professional health care treatments in conventional settings [
45]. Some sites such as Facebook have addressed this issue with group privacy settings that can be set to ‘secret’, so all group content is only visible to group members [
69]. Therefore, instead of generating and administering dedicated social networking sites and attempting to attract new members to it, a more practical and financially prudent approach may be to utilise existing social media platforms and user networks, with appropriate caveats and constraints, as the target group may already be within reach [
70]. Educating health professionals, patients and the public about social media may help to address issues surrounding privacy concerns as well as those arising from disseminating incorrect information [
45].