Bruce Lees death has been the subject of much speculation and debate. Here are the leading theories about what caused his death:

1. Cerebral Edema caused by Hypersensitivity to Equagesic: Bruce Lees death was officially ruled to be the result of cerebral edema caused by hypersensitivity to Equagesic, a painkiller.

2. Hyponatremia: A new study by kidney specialists from Spain hypothesizes that Bruce Lee died from a specific form of kidney dysfunction called hyponatremia, which is an abnormally low sodium concentration in ones blood. The study cites Lees "chronic fluid intake," use of marijuana, and documented factors that may have interfered with his kidneys function, such as prescription drugs, alcohol intake, and a history of injuries to the organ.

3. Heat Exhaustion: A 2018 book, "Bruce Lee: A Life," hypothesized that he died of heat exhaustion, but the current study did not find that temperatures were abnormally high that day.

4. Marijuana Use: Traces of cannabis were found in Lees stomach and small intestine when he died, according to a Post article dated September 19, 1973. As a result, some Hong Kong doctors believed that the brain swelling could have been brought on by ingesting marijuana.

It is important to note that while there are many theories about Bruce Lees death, the official cause of death was cerebral edema caused by hypersensitivity to Equagesic.