If you’ve ever visited Papua New Guinea you’ll have been struck by the friendliness of the people, and their welcoming smiles. You might also have noticed some of those smiles are red.

It’s caused by the chewing of “betel quid”, a mixture of unripe areca nut, mustard stick and slaked lime (calcium hydroxide).

Chewing betel quid is commonly practised by the Indigenous people of PNG and ingrained in their culture. It is used as way of greeting guests, a meeting snack and even a conversation starter.

The primary alkaloid found in areca nut is arecoline which stimulates the release of dopamine and explains the pleasant feeling chewing betel quid delivers. It may also be why betel quid can be addictive.

But arecoline is also categorised as probably carcinogenic to humans by the International Agency for Research on Cancer administered by the World Health Organization (WHO).

Betel quid’s other ingredients can affect the arecoline concentration, too. A study comparing the betel quid chewed in five regions of Indonesia found the highest concentration was in the mixture chewed by the people of the West Papua.

The WHO’s Global Cancer Observatory has estimated Papua New Guinea has the highest incidence rate of oral cancer among 185 countries, closely followed by........

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