1. Betel leaf with areca nut, slaked lime and tobacco is a popular type of paan that stains the mouth area due to profuse salivation. 2. Areca nut contains arecoline, a psychoactive alkaloid that affects the central nervous system and has addictive properties. 3. Chewing paan has significant health risks and can cause conditions like oral cancer, as well as systemic effects on multiple organs.