J.C.Staff founder Tomoyuki Miyata -- the anime studio behind popular works such as Revolutionary Girl Utena, Food Wars, Toradora and One-Punch Man Season 2 -- has gone into great depth about his career in anime production, revealing that the stress of it led to two-thirds of his stomach being removed.
Source:https://www.cbr.com/jc-staff-anime-studio-founder-work-stress-stomach-remove/