The market of sport supplement in the digital era: A netnographic analysis of perceived risks, side-effects and other safety issues

Background: The market of sport supplements is expanding worldwide. Such phenomenon is often supported by captivating marketing strategies and social media advertising providing unscientifically founded claims, thus raising safety concerns. The aim of our study is to provide a comprehensive analysis of the online market, patterns of use, perceived risks and other safety issues on supplement use as reported in online fitness communities. Methods: A mixed method approach was employed. An automatized web-based monitoring tool (Brand24®) was used to track the most popular supplements and related discussions according to the number of interactions between users and shares; the number and category of websites; the social media reach; and the most popular hashtags. Results were assessed through a netnographic qualitative analysis of online fitness fora, to identify motivations of intake, self-reported side effects andthe overall safety perception reliability of supplements information online. Results: A social media reach of over four million individuals, inclusive of 18595 posts, emerged from our search. The most cited supplements were “Whey Protein”, “Branched Chain Amino-Acid”, “Creatine”, “Multivitamin supplements” and “Nitric Oxide boosters”. Supplements were mainly taken for muscle gain (23%), increase energy (17%), and weight loss (8%). Although the web narrative on supplementation was overall positive, a wide range of side effects were reported by 19% of fitness fora users. These included acne (9%), water retention (9%), stomach pain (9%), rashes (7%), erectile dysfunctions (7%) and weight gain (5%). Concerns about contamination (47%), counterfeit content (17%) and the presence of hidden ingredients (11%) were also recorded. Conclusions: In a poorly regulated context, where unsolicited social media posts have replaced the typical advice provided by professionals, efforts should be made to ensure the reliability of the provided information to avoid the insurgence of unwanted adverse effects and safeguard public health.