Abstract:
Arecanut is the fruit / seed / endosperm of an oriental palm Areca catechu L. growing in most of the South and Southeast Asian countries. This nut is generally used for mastication by millions of people in different parts of the world as it is believed to have many medicinal properties. It is chewed mainly along with several other ingredients such as the leaf or inflorescence of Piper betel, calcium hydroxide, catechu, etc. Such combination of chewing product is commonly called as betel quid or pan. In India, chewing of arecanut or betel quid is a good old practice, the tradition of which goes back to 650 BC. Arecanut has very important place in religious functions in many Asian and Oceanic countries. This nut has also exhibited ample medicinal properties and most of them are now authenticated by proper scientific evidences. In China, there are already more than 30 medicines formulated and marketed using areca nut .In spite of such medicinal properties of areca nut, it is also tagged as carcinogenic by several researchers. It is equally true that there are several other contradictory research results which said that arecanut is not carcinogenic in normal dose but even cures cancer. Such reports are collected and highlighted in this paper.
Introduction:
Areca palm, Areca catechu L. (Palmaceae family) is an important commercial crop of several South Asian and Southeast Asian countries such as India, Indonesia, Myanmar, China, Bangladesh Thailand, Malaysia, Vietnam, Philippines, etc. The fruit or seed (endosperm) of this palm is called arecanut. In some parts of the world arecanut is misnamed as ‘betel nut’ as it is commonly chewed along with the leaf of Piper betle, a tropical, evergreen, perennial vine of Piperaceae family. Since time immemorial, arecanut is being used for chewing or mastication throughout the world, especially in Indian sub-continent and other parts of Southeast Asia as it is believed to have lots of medicinal properties. In India, the use of areca nut has been noticed as early as 1300 BC as cited by Sisu Mayana in ‘Anjana Chaitra’and the practice of its chewing from 650 BC as mentioned by Magha in ‘Shishupala Vadha’. In other countries such as Vietnam, the antiquity of areca nut even goes back to Bronze Age. In India, areca nut and betel leaf are considered as sacred and no ceremonial function is complete without them.
Arecanut has an important place in the ancient system of medicines in several countries such as India, China, Bangladesh, Philippines etc. The World Health Organization has listed out as many as 25 beneficial effects of A. catechu and included areca palm in the list of medicinal plants of Papua New Guinea. Most of the folklore medicinal properties of arecanut are now validated with proper scientific data. It has antioxidant, anti-inflammatory and analgesic, anti-diabetic, hypolipidemic, antibacterial, anti-fungal ,anti- malerial , anti-viral, anti-HIV, treatment for AIDS, anti-aging, treatment for Alzeimer’s and anti-ulcer, anti-migrain, antihypertensive ,antidepressant, anti-allergic,anthelmintic, aphrodisia,anti-venom, hepatoprotective , cytoprotective , etc. In China as many as 30 medicines prepared using arecanut as one of the ingredients are already in the market for the treatment of several disorders of man. In India, two to three ayurvedic preparations containing arecanut are advocated by doctors for the management of diabetes. Though arecanut has got all these beneficial properties, several researchers highlighted that arecanut chewing might cause cancer.
The adverse effects reported in association with arecanut chewing might be due to several other factors such as small sample size, the role of other ingredients used in the preparation of betel quid, the quality of arecanuts (including contaminations and adulterations) used for making different preparations of chewing products, etc . Ironically, these factors were not taken into consideration or discussed at all in most of the publications which said that arecanut chewing was dangerous, but simply blamed arecanut for all the ill effects. There are several other contradictory reports which said that arecanut as such was not cancerous but cures cancer. Such reports are collected by searching text books, old journals, PubMed, Google Scholar, and Science Direct, etc. and presented in this bibliography. This gives an insight for further detailed research in this field.
According to laboratory evidence;
Using arecanut
Certain studies carried out on laboratory mice (A/Iisc strain) International Journal of Medical and Health Research 36 confirmed that the extracts of arecanut (prepared from 100g of arecanut powder) and betel quid without tobacco (extract of the mixture containing 100g of betel leaves + 50g of arecanut powder + 4g of lime) were not carcinogenic. The authors arrived at this conclusion by applying these extracts to both normal as well as immune suppressed mice for two years. The extracts did not induce any tumor in both the conditions. The irony is that this paper was not discussed in most of the review papers on the carcinogenicity of Arecanut. According to Arecanut research and development and foundation, Mangalore can give reports to central laboratories of Delhi among arecanut donot causes cancer and it cures cancers.
Using pan masala
Ramchandani et al. did not notice any tumor development on the skin of mice (ICRC strain) when it was pasted with 50mg of pan masala (without tobacco) extract continuasly for 40 weeks. Similarly, administration of 50mg pan masala extract by gavage did not develop any tumor in any of the internal organs of the treated mice. This dose comes to about 1.7g of pan masala/kg body weight of the animal.
Using betel quid without tobacco
In Taiwan, the betel quid generally consists of a bisected fresh green arecanut (including the husk) sandwiched with a spike of betel vine and a brown paste containing slaked lime and catechu. The effect of such betel quid on the cheek pouch of hamster was studied by inserting 1.5g of such betel quid into the cheek pouch for 52 weeks. Treatment with the chemical carcinogen, DMBA (7, 12-dimethylbenz (a) anthracene) for 6 weeks developed 11-70% carcinoma whereas; treatment of such betel quid alone during the entire period of experiment (52 weeks) or further followed by 10 weeks treatment with that chemical carcinogen did not lead to any tumor. This proved that Taiwan betel quid is neither a carcinogen nor promotes carcinogenic activity.
Studies on human population
Pan chewing without tobacco is not a risk factor for cancer
In a study conducted on the etiological factors in oral squamous cell carcinoma in Madras, India, it was reported that 85% of cheek carcinoma patients were chewing betel quid with tobacco as against 12.5% in the control group. On the other hand, only 8.7% of cheek cancer patients were pure betel and arecanut chewers as against 51.8% in the control group. The lacuna is that, no data for non-chewers were given in this study. In a study conducted atour region that is Bangalore, India on the occurrence of cancers of oral cavity in pan chewing people in that region, Nandakumar did not notice any increase in oral cancer in those people who chewed pan masala without tobacco. Of the 348 cases of cancers of the oral cavity and an equal number of controls, the relative risk due to pan chewing without tobacco was found to be non-significant with both males and females (p=0.36 and 0.17 for males and females, respectively) whereas it was significantly more (p=0.001) with pan chewing with tobacco.
One indirect evidence is there,
Wound healing property of arecanut.
Topical application of arecanut extract was reported to increase the wound healing process significantly in treated animals. In a study conducted on Wistar albino rats it was reported that 2% arecanut extract significantly increased the wound contraction rate compared to that of control and was found to be similar to that observed in test drug treated animals. Further, the arecanut extract was also found to overcome the wound healing suppressive property of dexamethasone.
Conclusion
All these reports confirm that arecanut in its pure form is not dangerous but has got a plethora of medicinal properties including curing ulcers, wounds and even cancer. Most of its folklore medicinal properties are now validated by scientific evidences. Detailed studies on the nature of active principle(s) responsible for all these properties and clinical trials on them are warranted to utilize such plant products effectively and profitably as these palms are available in plenty in most of the South and Southeast Asian Countries. Care should be taken not to combine arecanut with any of the harmful materials and blame arecanut for the ill effects of such combinations.
