Six-Day War (fast)
The Six-Day War was a six-day long period of suicidal ideation at FCC Petersburg Medium circa 2011, while Nathan Larson was cellmates with Matthew Newingham. At the end, Newingham expressed concern about Larson's not eating, and Larson figured Newingham was likely to report him for it, so he resumed eating.
During the fast, Larson didn't eat or drink anything at all. It was the longest period of not consuming any liquids that Larson ever had.