Carcinogenic Effects of Chewing Betel Nut
Betel nut is actually the fruit of areca. Areca is a species of palm found in the tropics of Southeast Asia and on the islands of the pacific. Betel is derived from the betel pepper plant also found within the pacific region. The practice thus is that chewers of these fruit usually wrap this areca fleshy fruit in a betel pepper leaf and garnish it with sweeteners, spices and mineral lime which is a type of stimulant with alkaloid properties.
Though betel nut sales rakes in billions of dollars across the globe, its medical implication on the chewers have become a source of concern to health experts due to the discovery of the carcinogenic effects it has on the oral health of its chewers. Let us examine the health implications of chewing betel nut.
For several centuries, Areca nut has been used in cultural and religious festivities in parts of Asia and the chewers of this nut usually explain that they have a feeling of wellbeing, excitement and euphoria after chewing it! Medical experts maintain that the alkaloids in this nut can elicit a habitual instinct and make the chewer addicted to it. Furthermore, the teeth of betel nut chewers become reddish brown in color as a result of the stain contained in the alkaloids.
Betel nut addicts can develop a fatal condition known as chewers’ mucosa which is a reddish-brown stain of the mucous membrane. These chewers can also develop a certain chronic oral mucosa referred to as oral submucous fibrosis. Most important of note, betel nut chewing can progressively lead to the emergence of a type of oral cancer known as Oral squamous cell carcinoma. This could be the reason why there is a high rate of oral cancer cases in Southeast Asia including Taiwan and Papua New Guinea.
Carcinogenic Effects of Chewing Betel Nut
Chewing betel nut (also known as paan and gutkha) is deleterious to the oral soft tissues. It promotes nonmalignant odontogenic disease and contributes to carcinogenesis.
Although Taiwan has made progress in reducing betel nut use with nationwide education outreach and cessation courses, it remains widespread throughout Asia. This is especially true in working-class communities where chewing is culturally accepted.
Oral Cancer
The habit of chewing areca nuts is a serious threat to the health of hundreds of millions of people worldwide. It causes oral submucous fibrosis and leukoplakia, precancerous conditions in the mouth that can lead to cancer of the lips, tongue and throat. The areca nut itself, and the ingredients in betel quid including tobacco leaf, katha and slaked lime, are carcinogenic to human beings. The combination of these chemicals with saliva and the act of chewing produce high levels of oxidative stress which damage cellular DNA. Both areca nut extract and arecoline induce c-jun proto-oncogene expression in human oral mucosal cells, contributing to their carcinogenicity. In addition, the slaked lime and betel nut together produce reactive oxygen species that oxidize cellular proteins, thereby inducing cell cycle-related changes and mitochondrial dysfunction.
The potential for betel nut consumption to cause oral cancer has led to several government-led efforts to control the habit, most recently in Papua New Guinea. In 2013, physicians and other public health officials managed to get a ban on the sale of betel quid in Port Moresby, but it hasn’t yet been extended to the rest of the country, where the problem is particularly severe.
Oral cancer is the most common cancer in Papua New Guinea, and many of those diagnosed die from it. The high incidence of oral cancer in Papua New Guinea is associated with the use of betel nut and cigarettes, which are also linked to poor economic status and a lack of adoption of healthy lifestyle habits.
A study conducted in a small sample of adults from the region around Port Moresby found that the betel nut habit was linked to the presence of oral lesions, which could indicate precancerous growths. Within-sample alpha diversity was lower in current betel nut chewers than in past or never betel nut chewers, and specific genus-level Streptococcal OTUs were higher in those with oral lesions. In addition, genus-level Actinomyces OTUs were significantly lower in those with lesions. This may indicate that betel nut chewing changes the microbiome of the mouth in ways that contribute to the development of oral premalignant lesions.
Oral Submucous Fibrosis
The betel nut is a popular chewing substance in many Asian countries. It is made up of green piper betel leaf, areca nut, and slaked lime and is then covered with a mixture of spices. During chewing the thick fibers injure the oral mucosa causing inflammation. This activates macrophages to secrete cytokines, which initiate the fibrotic process that leads to OSMF. The cytokines that are secreted cause excessive collagen production and disrupt the normal balance of collagen homeostasis in the oral cavity. Over time the abnormal collagen deposition becomes calcified and hardened which creates the characteristic bluish color of the lesions.
Initially, the lesions present as a blanching of the buccal mucosa that has an irregular cobble-stone appearance. As the disease progresses the lesions become palpable and form fibrotic bands that restrict the patient’s ability to open their mouth, which is known as trismus. This restriction in the opening of the mouth also makes it difficult for the patient to eat or speak and can cause xerostomia (dry mouth). In some advanced cases, the lesions may extend to the lips, retromolar areas and soft palate and occasionally to the pharynx and esophagus.
Oral submucous fibrosis has been associated with systemic diseases such as coronary artery disease, chronic kidney disease, and gastrointestinal complications such as gastroesophageal reflux and peptic ulcer. It is also associated with oesophageal squamous cell carcinoma.
The best way to prevent OSMF is by avoiding the consumption of betel nut and other smokeless tobacco products. Local health and medical institutions should focus on spreading awareness of the ill effects of betel nut chewing and educate the population to avoid it. In addition, it is essential to promote a proper diet and nutrition. Moreover, scientific research should be focused on the etiology, diagnosis, and treatment of OSMF in order to decrease its incidence, recurrence rate, and malignant transformation. A comprehensive understanding of the pathogenesis of OSMF will contribute to its prevention and development into a promising therapeutic approach.
Gum Irritation
Betel nut, also known as areca nut, grows in tropical parts of Asia, Africa and the Pacific. It is chewed as a stimulant and a digestive aid. It may be eaten alone or as part of a “betel quid” (a mixture of thinly sliced areca nut, tobacco, slaked lime and spices or flavorings wrapped in a leaf). Chewing Betel nut causes gum irritation, which can lead to tooth decay and gum disease. In addition, it increases the risk for esophageal and lung cancer. It also can cause hyperlipidemia, which is elevated levels of fatty substances in the bloodstream, and irregular heartbeat, which is often called “a-fib.”
Betel nut chewing can also contribute to diabetes by interfering with the body’s normal insulin production. The slaked lime in betel quid can also create hundreds of tiny abrasions on the teeth, which can allow the penetration of cancer-causing agents into the mouth.
Studies have shown that long-term chewing of betel nut is associated with an increased risk for oral cancer, periodontal disease and precancerous lesions on the gums. This increase in the risk of these diseases is due to the direct chemical and physical actions of betel nut components on the dental hard tissues and soft tissues of the oral cavity.
Various factors, such as genetic predisposition to cancer, diet and body structure can also influence an individual’s susceptibility to the carcinogenic effects of betel nut.
Although there are some exceptions, most people who use betel nut have no idea that it can cause oral cancer. Increasing awareness about the dangers of betel nut and its ingredients, along with public health programs that educate people about how to quit, can help reduce the thousands of deaths caused by this centuries-old habit. It is also important that doctors and dentists ask patients if they chew betel nut, especially those from areas with large Asian populations. This way, doctors and dentists can screen for this serious disorder and provide effective treatment when it is needed. Treatment for betel nut addiction will usually include detox and group or individual therapy to address the underlying mental health issues that contributed to drug abuse.
Tooth Decay
Betel nut (Piper betle) and its chewing variant called betel quid (BQ) are used as socially endorsed masticatory products around the world. This habit of BN/BQ chewing has strong etiological links to human susceptibility to diseases, including oral and oropharyngeal cancers, and it is associated with oral submucous fibrosis. The fibrosis causes yellowish white lesions of the palate and buccal mucosa. Histologically, the lesion is characterized by vitrification of subepithelial connective tissue and chronic inflammatory cell infiltration with increased fibrotic changes.
In addition, it may contribute to the development of periodontal disease. Studies have found that the chemicals in betel nut change cell functions and increase enzymes that lead to carcinogenesis. The substances found in areca nuts have mutagenic, cytotoxic and genotoxic properties that can disrupt human DNA and damage the oral cells.
It is important for dentists to educate their patients about the effects of betel nut chewing on dental hard and soft tissues. Educating patients about this harmful behavior and encouraging them to stop the habit may prevent some of the health complications associated with it.
The onset of betel nut-related problems can progress from relatively minor ones, such as white or red lesions inside the mouth to grotesque flesh-eating tumours that cause great pain and discomfort. For many Taiwanese men like Qiu, the resulting oropharyngeal cancer is not only physically debilitating but psychologically devastating as well.
Despite public awareness campaigns and a sharp rise in the number of people diagnosed with oral cancer, most chewers are not changing their habits. In fact, in some regions of the country where betel nut is most popular, the incidence of the disease has doubled since the early 1980s, coinciding with a rise in popularity for betel nut and chewing tobacco.
The government has been implementing measures to reduce the use of areca nuts, but it is not yet clear whether they will be effective in reducing the rate of oral cancer. In the meantime, doctors and dentists in areas with a high proportion of Asian populations should consider adding questions about betel nut use to their patient questionnaires.
