UFC (Ultimate Fighting Championship) is allowed because it is a regulated sport with strict safety and health guidelines for fighters. The UFC also requires the use of protective headgear, gloves, and other safety equipment to help protect and minimize the harms of the sport. Aside from the precautions taken to protect fighters, the UFC also focuses on creating a set of fair and balanced rules to ensure the athletes are able to compete in a safe and professional manner. Furthermore, the regulations and safety measures in place help to keep the sport popular and attract viewers, while providing a unique form of entertainment.