University of Hawai'i Cancer Center connection: Areca (betel) nut consumption: an underappreciated cause of cancer.

The fruit from the palm Areca catechu (L.) commonly referred to as areca nut (AN) is botanically a drupe fruit with an outer leathery part (exocarp or skin; and mesocarp, which can be fleshy or hard) that surrounds a shell (hardened endocarp with a seed or pit) at all times during ripening (Figure 1). ANs in their variable preparations, commonly wrapped in a betel leaf therefore the widespread name “Betel nut” (BN; see below), are consumed worldwide by an estimated 600 million people among all age groups and social classes with prevalent consumption throughout the Indian subcontinent, East and Southeast Asia, and the Pacific Islands.1,2 In Guam, AN chewing is widely practiced among many populations (including Chamorros, Yapese, Palauans and Chuukese), and approximately 11% of Guam's population chew on a regular basis.3 In some areas of India, the frequency of AN use has been increasing among the youth and has been speculated to serve as a gateway for tobacco use.4,5 Figure 1 Base ingredients of a Betel quid: areca nut, Piper betle L. leaf, and slaked lime (which may be powdered - as shown, or in liquid or paste form). Chewing tobacco or tobacco from cigarettes is often added according to preference in addition to other ingredients ... There is considerable variation in the way ANs are consumed. They can be chewed alone, wrapped in a leaf of the betel pepper (Piper betle L.) then referred to as BN, or as a “betel quid” (BQ), whose recipes, despite varying regionally and locally within countries, generally consists of a whole or portion of an AN wrapped in a leaf of the betel pepper (Piper betle L.) together with other additives such as slaked lime (calcium hydroxide) and sometimes tobacco (from chewing tobacco or cigarettes) (Figure 1) and/or spices.6–9 Lime is typically obtained from the burning of coral or shellfish or extraction from limestone and is sold in paste, liquid, or powdered forms (Figure 1).7,8 Other ingredients such as cloves, cardamom, alcohol, nutmeg, aniseed, ginger, and sweeteners such as coconut are sometimes added to the various AN preparations for extra flavoring according to preference.7,8,10 In many countries such as those in South Asia, proprietary BQ mixtures are commercially manufactured and heavily advertised towards youth.11,12 Oftentimes, the nut is conveniently sold in proximity to tobacco products as to indirectly promote its concurrent use (eg, selling of single cigarettes).13 The chewing of AN in its various preparation forms is a socially accepted habit in many countries of the Western Pacific region13 and is used as a means of promoting social relationships and community ties. This habit also has cultural and religious significance among some populations where chewing is endemic.1,7,14 Factors thought to influence chewing commencement include encouragement from family members, friends, or role models at a young age, as well as peer pressure; in addition, some users have described AN chewing as a way to pass time or avoid boredom and loneliness.1,13,15