ABSTRACT
BACKGROUND: In Germany, widespread use is made of dietary supplements (DS) to improve the individual health status, especially among patients diagnosed with certain conditions, elderly people and athletes. Legal aspects as well as health risks related to DS purchased via the internet are rarely analysed in Germany. PURPOSE: We aim to provide a review of the respective literature focusing on health risks, legal aspects und consumer information related to the internet retailing of DS. METHODS: A review of the literature including reference tracking was conducted between January 2017 and January 2018 and combined with the results of an analysis of legal regulations in Germany. RESULTS: Using the internet to research into health-related aspects is common among patients. However, this is often associated with a lack of individual and professional counselling regarding the potential risks and benefits of using DS. Potential side-effects are often not declared, and there is a high prevalence of contamination with harmful substances, especially among DS marketed as "natural health products". Athletes must be aware of the risk of being tested positive due to contamination of a DS with a WADA-banned substance. CONCLUSION: Questions regarding the use of DS in patients as well as in healthy athletes should be implemented into the medical history records by physicians. The use of DS should be carefully documented. A thorough cost-benefit analysis is recommended, and athletes should consider the risk of being tested positive.