Following the exponential increase in Internet use over recent decades, social networking sites have become a major source of information and inspiration. These networks have a crucial role in defining beauty standards and sharing new trends and ideas, especially among adolescents and young adults. The concept of ‘fitspiration’ (a combination of the words ‘fitness’ and ‘inspiration’) encourages people to engage in physical activity and adopt a healthy lifestyle. This chapter discusses how fitspiration’s emphasis on well-being, having a fit body, and healthy lifestyle has made potentially pathological behaviours, such as dietary restriction, substance misuse, and overexercising, socially acceptable. The potential physical and psychological risks to fitspiration users, including unsupervised supplement intake, body image disturbances, eating disorders, physical and mental burnout, social isolation, and feelings of weakness and worthlessness, are analysed. The need to further elucidate the potentially harmful effects of social network content and develop preventive mental health strategies is highlighted.