Nicotine. Caffeine. Betel nuts. You may never have heard of them, but nuts from the Areca palm are hugely popular as a chewable stimulant: Almost a tenth of the global population enjoys them, the BBC reports.
A millennia-old tradition, they're the world's fourth-most-popular psychoactive substance, Healthline adds. Their effect is similar to that of drinking six cups of coffee, and many workers engaged in lengthy physical tasks chew them to maintain alertness.