Why? Because, he thinks it helps ease pain. After experiencing severe chest pain in 1969, and having no relief with “real” medicine, Chen started drinking fuel, and never looked back Experts estimate that he’s drank around 1.5 tons of fuel over the past 42 years. Yikes.
Obviously, doctors have been skeptical about Chen’s health, but a health screening showed that he wasn’t showing any signs of gasoline poisoning or toxicity. They’re estimating that he must have developed some sort of immunity to the toxic hydrocarbons, because otherwise the 71 year old man should theoretically be dead.