Abstract

Dietary supplements are widely consumed to address perceived nutritional inadequacies and promote health. In recent years, social media platforms have emerged as influential channels for the marketing of dietary supplements. These promotions often disseminate unsubstantiated health claims and may contribute to inappropriate or excessive supplement use, raising concerns about population-level health risks, particularly among young adults. A rapid review was conducted in accordance with updated Cochrane guidance for rapid reviews of effectiveness. Systematic searches were performed in PubMed, Google Scholar, and CINAHL to identify peer-reviewed studies published in English within the past 10 years. Studies examining social media exposure, dietary supplement use, and health-related behaviours among U.S. adults aged 18–50 years were eligible for inclusion. Data were extracted and synthesized narratively due to heterogeneity in study designs and outcome measures. Across included studies, exposure to dietary supplement content on social media was consistently associated with increased body image dissatisfaction, heightened susceptibility to persuasive marketing and greater likelihood of unsupervised or non-evidence-based supplement use. Young adults frequently reported modifying dietary practices or health behaviours in response to online content rather than professional medical advice. This review highlights the growing public health implications of social media–driven dietary supplement promotion. The findings support the need for enhanced regulatory oversight of online supplement marketing, improved health literacy interventions, and more proactive patient–provider communication regarding supplement use. Future research should prioritize longitudinal studies to evaluate the long-term health outcomes associated with socially mediated supplement consumption and to inform evidence-based policy development.