Betel nut is a common plant fruit that is usually chewed. Betel nut contains many chemicals, including irritants such as betel nut alkaloids. When betel nut is chewed, saliva in the mouth mixes with the betel nut to form a reddish juice. This juice contains irritants and can have adverse effects on the mouth and digestive system. Swallowing the water chewed out from betel nut can lead to discomfort and health problems. Ingredients such as betel nut alkaloids can irritate the throat and esophagus, causing inflammation or other discomfort. Long-term betel nut chewing is also associated with an increased risk of oral cancer and other health problems.