PURPOSE: To determine the effectiveness of social media-based interventions in promoting positive changes in nutrition behaviors amongst adolescents, and identify the behavior change technique(s) (BCT(s)) that were used in effective interventions.
METHODS: MEDLINE, Embase, PsycINFO, Cinahl, and Cochrane library were systematically searched. Eligible studies included: participants aged 13-18 years; use of one or more social media platform(s) in the intervention; a comparison group not exposed to the social media-based intervention; nutrition- and diet-related behavior outcome(s); and an experimental study design. BCTs were identified using a behavior change taxonomy. Quality and risk of bias assessments were also conducted.
RESULTS: Seven eligible interventions were included, varying from internet-only programs to in-person programs with internet or website-based component(s). Studies used relatively outdated forms of social media such as purpose-built discussion boards or chat rooms rather than commercial social media interfaces (e.g. Facebook). Five of the seven interventions demonstrated improvements in at least one nutrition behavior. The most common improvement was for fruit or vegetable intake, and two of four studies showed improvements for sugar-sweetened beverage consumption. The most common BCT used was social support, followed by demonstration of behavior, self-monitoring, goal setting, and feedback.
CONCLUSIONS: The current evidence base is equivocal with respect to changing overall dietary behaviors, as increasing intakes of desirable food groups were more successful than decreasing unfavorable food habits. Further research using better quality interventions, full description of the BCTs, long-term follow-up, and popular contemporary social media platforms to build the evidence base are required.