It is a rumor that betel nut causes cancer. It is really Chinese medicine. CCTV's "Yangshengtang" also invited Professor Li Liukun from Beijing University of Chinese Medicine to do the program. In the program, the professor said that betel nut is "one of the four major medicines in South China", and soaking in water can help to excrete wet poison from the body, so personally, eat areca is harmless.