Up until the 1980s, scientific consensus held that stomach ulcers were caused by stress and spicy food. Australian scientist Barry Marshall thought differently, and to test his theory he drank a cup of bacteria.
Marshall and another scientist (Robin Warren) discovered the bacterium Helicobacter pylori growing in the human stomach in 1982. This in itself was revolutionary, as the stomach was previously thought to be too hostile an environment for bacteria to grow. Marshall theorized that the bacteria could contribute to gastritis and peptic ulcers – but then he had to prove it.
At first Marshall and Warren tried infecting pigs, but when that didn’t work Marshall decided to experiment on himself (eek!). He drank what Wikipedia describes as a bacteria “broth” (ew!) and awaited results. They came quickly: in three days his mother commented on his terrible bad breath. Two days later, he was vomiting. Three days more, and tests showed that he had terrible gastritis – and his stomach was teeming with H. pylori bacteria.
For this work, Marshall and Warren were awarded the 2005 Nobel Prize in Medicine. And everyone can relax when they eat spicy food.