Gustav III of Sweden's coffee experiment was a purported twin study ordered by the king to study the health effects of coffee. The authenticity of the event has been questioned.[1] The primitive medical study, supposedly conducted in the second half of the 18th century, failed to prove that coffee was a dangerous beverage.
- ^ "Coffee – rat poison or miracle medicine?". Uppsala University. Archived from the original on 6 October 2022. Retrieved 6 February 2012.