Betel-quid chewing is common in South Asia, South-east Asia, and the Pacific Islands, especially in our country. Betel-quid contains various ingredients, including areca-nut, tobacco, betel leaf, betel vine, inflorescence, slaked lime, and some special flavored substances. The composition and processing of betel-quid vary in different countries. However, areca-nut and tobacco are consistent main components. Areca-nut contains betel alkaloid, tannin betel nut, betel nut-specific nitrosamines, and reactive oxygen, which exerts cytotoxic, genotoxic, and carcinogen effects. Previous studies showed that betel-quid chewing is a significant factor contributing to oral submucous fibrosis and is related to the incidence of oral cancer, leukoplakia, lichen planus, and so on. This paper presents the prevalence of areca-nut consumption, ingredients, and carcinogenic mechanism to provide a scientific basis for oral cancer prevention and awareness.
